02 prizm with 2 codes po420 and po135 i already changed both 02 sensors and the cat engine light is still on and its getting expensive i need help figuring this out?
the po420 could also be a misfire or vacuum leak
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If you changed plugs wires forward 02 sensor and throttle sensor but your 200 Ford Escort is still running idleing rough what do you do next?
you might want to check your egr valve. if it's stuck open and leaky just a little bit it will almost kill the engine. it's easy to check if you have a vacuum pump. they are cheap and available at any auto parts store. the procedure is in the chiltons manual. if you need more detail just yell. I'm h…aving a similar problem. my idle is going up and down randomly. i'v checked every sensor that i can and everything checks out good. while testing the idle air control valve i found it was making the idle change but it was because its signal voltage was changing. the only thing i haven't changed is the pcm. any ideas? Reset error codes, Oxygen sensor is ignored if old errors are not cleared. The idle going up and down, depending upon how erratic, may be normal behavior during the warm-up process. Check the timing belt and make sure that the timing marks are still in alignment. Unfortunately checking the timing mark on the crankshaft requires removing the damper. Otherwise it'd be cake. Could be MAF (Mass Air Flow) sensor. Located between air cleaner box and throttle body. I was having the same problem I unplugged the MAF sensor and it ran better. So, I replaced it and it ran even better yet. I replaced the fuel pump and fuel filter before that. But, it still ran rough. I tested fuel pressure and it was fine. (MORE)
What should you do if the shop says your 2000 Metro with 155k miles needs a new cat converter and 02 sensor but that's expensive and it runs fine?
My sense is that these components last somewhat longer than firstanticipated, probably because of the leaner mixtures we're using,and the no-lead gas. It can be expensive. But you probably couldchange out the oxygen sensor yourself. It's usually accessible, andit ain't brain surgery. The converter i…s another matter. Good Lucki had a metro with 250000 with original convertor and 02 theconvertor is built into a section of pipe you get the whole thingfor 150$ and replace it with four bolts and believe it or not thebolts usually are removable without having to use a torch (MORE)
Answer . I changed my downstream sensor by driving the car, 2000 Alero, onto ramps then I set the emergency break. I disconnected the battery to reset the computer before I removed the sensor. The sensor on this car was located on a short pipe between the converter and the muffler. I guess tha…t there is a special socket to remove the sensor but I just grabbed the nut of the sensor with a pipe wrench, since I was replacing the sensor anyway. With the extra pulling power of the big wrench the sensor screwed right off. I carefully pulled the cable of the sensor away from the clips all the way up to the connector. The connector had a safety clip which pulled out, then the electrical connector is pulled apart by bending down the plastic side clip of the bottom connector. I replaced the new sensor using care not to break the wires. Then I worked backwards replacing the cable the same way that I removed the old one. (MORE)
You have a 1996 Ford Windstar which sensor would you need to change if your error for the check engine light reads bank 2 sensor 2?
Answer . The sensor in question is the downstream catalyst monitor (O2 sensor) located on the exhaust pipe that comes off of the front exhaust manifold.. But we really need to establish something so that you do not replace parts unnecessarily. A fault code from a sensor, especially an O2 sensor … NEVER automatically means the sensor is bad. It means the PCM (main car computer) sees a reading that it doesn't like from that sensor. . In the case of an O2 sensor code, it means that the O2 sensor is either too rich or too lean, or not responding fast enough to suit the PCM. It could be a bad O2 sensor, or what usually is the case, is that there is a problem that is forcing the O2 sensor to read out-of-normal range, something like a vacuum leak, engine misfire, or in the case of your catalyst code, a bad catalytic converter. . The funny thing is, that you may actually replace the catalyst monitor (Downstream O2 sensor), and erase the code, then drive it, and think that you've fixed it, but you haven't. That particular code is a low-priority code, so it takes several consecutive drive cycles with that same problem, to get it to turn the light back on. . Don't blame Ford, blame the EPA. They are the ones who decided that the system has to operate this way for all cars sold in the US. (MORE)
If there is a code for map sensor and 02 sensor does this mean the cat converter is bad or plugging up?
'88 o2 sensor not grounded. if the sundance is an 88 it will have a three prong lead. Plymouth realized that it was not getting enough ground (mopar EEK forum) I've wrapped a wire aroung mine and ran it directly to the negative terminal. code 52 is gone. As to the map senor. try this forum http://m…opar.kmzefamily.net/ecu/index.HTML check it out and let me know. how does the car drive? * the easiest way to test for a bad conerter is to unplug ita t the manifold. you will need two new bolts since the old ones will snap off. take for a drive. Warning, it will be VERY loud. bring license and registration, as well as a good story. before heading out clear all codes by disconnecting negative terminal for 10 seconds. if at the end of the trip the codes are gone, then you have your answer. (MORE)
Where are the 02 sensors on a 96 48L 8cyl thunderbird and what are some signs when they need to be change?
Answer . \nthe o2 sensors are located one in front of the cat and one behind,usually when a check engine lite comes on you have an emissons problem i go to Auto Zone and they can tell you what engine code tripped on your check engine lite.they usually try to sell you the part you need it pays to …shop around for what you need.hope this helps. (MORE)
You have a 2001 Nissan Pathfinder se and the check engine light is on you have been told it is bank 2 sensor 2 downstream 02 oxygen sensor which sensor is this and how difficult to do?
Answer . I have the same car & just changed it myself. It's the driver's side, when standing in front of the car, you should see a red cable that connects on the right side of the engine & runs behind & down then twists into the exhaust pipe next to the cat. The bad part after getting the sensor… out of the pipe is removing the 2 clips that run down & behind before the cat. The other clips aren't so bad because they aren't in a cramped hole. I thought next time I might try large sharp toenail clippers to snip them off..... Got a $90.00 sensor from advance auto. I've read that this requies reprogramming from Nissan, but I'm not too sure how needed it is. The Nissan guy told me you don't always need to regrogram, but that is another $87.00.. I changed mine the problem improved the code went away, I'm still trying to sort out other codes but I think I got this one taken care of. (MORE)
Why would emission code P0420 still be coming on in a 2002 Chevy Impala if you already changed the catalyst converter both O2 sensors and the coolant sensor?
Answer . \nYou have the code P0402 which is Catalyst System Efficiency Below Threshold (Bank 1). You are throwing parts at the problem without actually knowing what is wrong. This could be nothing more than a simple vacuum leak, a malfunctioning EGR valve, or carbon buildup in the EGR system, and… a few other things. Take it to someone who has the skill and expertise the find the exact problem. (MORE)
How to install a 02 your abs light has came on and the mechanic hook it up on the machine and it indicated that you need a 02 sensor?
The "ABS" light is telling you that you have a problem with your antilock brake system. The 02 sensors monitor your engine's performance and emissions. these are two completely different systems. I suggest you look for a new mechanic.
When changing the 02 sensors and the spark plugs on a 1998 Nissan Maxima why would the service engine soon light still come on?
Have the service engine soon (check engine), same thing light scanned to know exactly what is the problem. You may purchase a cheap scan tool at some car shops like Canadian tire and scan the code yourself. Obviously make sure to change the defective parts with good parts and cancel the code afterwa…rds. I hope this was helpful. (MORE)
2001 Pathfinder engine light problem you replaced 2 oxygen sensors then replaced 2 timing sensors the service engine light still on computer shows no code?
Wrong scanner?? If a check engine light is on, there are codes. Timing sensor? Check engine usually means a problem... Service means that scheduled service needs to be performed like oil change, or timing belt replacement. I would Check your Catalytic Converter. What often happens is the catalys…t that is in the Catalytic converter Heats up and Blows out into your Muffler. This means It is not the sensor,but your converter and Muffler Need Replaced.I have just fixed two cars with this problem,and they had the same symptoms,Check engine Light. (MORE)
1996 ford f-150 4x4 351 ci your service engine light was on when you got the truck you checked for the code it said your 02 sensor was bad so you brought two of them installed them the lights stay on?
Answer . \nTry disconnecting the battery for 10 minutes to see if it will reset--if not have engine scanned. Answer . \nTry disconnecting the battery for 10 minutes to see if it will reset--if not have engine scanned
My 2000 ls has the check engine light on. It reads lean and i replaced both front 02 sensors but light still comes on. The car runs fine but turns off at idle regardless if in drive or park. HELP?
Answer . \nSince you didn't mention the make or model of the vehicle, you will have to look at the following... A lean O2 sensor does not usually mean that the O2 sensor is bad. Since your idle is bad, you need to look at other air/fuel controls such as EGR, MAF, MAP, IA, injector nozzle and a…nything else that would either restrict air or fuel at idle (MORE)
Answer . \nMaybe the sensors you changed out were not the problem. Post what the symptoms were, what the codes were, and why you changed out what sensors you did. Sometimes errantly the wrong part is diagnosed as being defective, like having low fuel pressure and people spend $500 for fuel inj…ectors when in reality it was a clogged fuel filter for $10\n. \nSome cars take a few starting cycles or cycles of driving before they reset the check engine light. If you had someone read your codes, normally they have the ability to turn off the check engine light.\n. \nIf you replaced the incorrect part(s) then your check engine light will remin on until the part casuing the fault is replaced. I hope the parts you replaced were the problem and it's just a matter of havign the check engine light turned off.\n. \nIf not, repost and maybe we can direct you. Todays' engines are not like ones of old where you can throw parts at it and "feel" you got it fixed. It's either fixed right or the check engine light is there to remind you it isn't. (MORE)
Questions with 'The O2 Sensor Light Comes On After 90k Miles And A Screw Under The Gauges Needs To Be Removed And Placed In Another Hole Either That OR Drive Another 90k And It Will Turn Off Its Stupid I Know'
You replaced your 02 sensor for Monte Carlo 1999 you still get engine light what else could it be possible?
Answer . The check engine light means that the computer has a problem code that you need to read. Use a diagnostic code reader for your vehicle. Your Chevrolet should be OBD2 compliant, meaning that you need an OBD2 code scanner.
What would cause a 96 t100 to run very rough i have already change plugs wires 02 sensors and it doesn't appear to have air intake leak computer says 2 cyl. misfire any ideas?
Check under the hood at night or in a dark garage for spark arc. Mine would arc or ark from the spark plug wire to the coil on the passenger side of the motor. Spray with WD 40 or silicone to stop the ark then replace the coil and or wires. About $60 for the coil and 50 for wire set. You only get th…ree wires in the set. You don't need the ones on the one side as they are built with the coil. . It could be a bad coil pack (black thing above 3 of your spark plugs) I had one go bad and it caused a miss in the engine. (MORE)
Your engine light is on your 2000 mit galant reading is P0170-fuel trimline 02 sensor was replaced light still on. What else could be checked?
If a sensor it 'tripped', once it is replaced, you need to reset the computer to eliminate the 'check engine' light. Mitz. recommends you take it to them to have this done at a cost of $15.00, but you can pull the negative power line from the battery and it will do the same thing.
You have a volkwagon jetta vr6 2000 2.8 manual trans my check engine light came on you had the cat changed and both o2 sensors 250 miles later my light came on again 0420 CODE?
well I read about this happening somewhere else I cant really recal it but from what I remember the o2 sensors where changed and then there is a problem in the wiring with o2 sensors
1999 jeep sahara change both oxygen sensors engine light still coming on with rear flank on the computer?
Answer . \nI dont know what codes you were getting. double check the connections. And get the code cleared. retry it. If it still comes on reread the code to see what it says. You didnt get anything on tips of the o2 sensor did you? \nAnother thing the rear one refers to the one after the Cat co…nverter. Is that the one that was replaced? People sometimes forget this. If there is still a probplem the circuit has a prblem. The code would be saying this though. Hope this helps. (MORE)
Check engine . \nFirst you must know that replacing the O2 sensor is what is needed to repair the problem indicated by the check engine light. Then you need to be sure that you replaced the right sensor( most vehicles have more than one). If all this has been done give the computer a chance to re…adjust, it usually takes about 50 miles of driving before all the different systems are ready to report properly. (MORE)
Answer . \nThe oxygen sensor reports live information about the engine's air/fuel mixture to the powertrain control module,(Computer). This information is used primarily to help calculate fuel delivery to the engine, which changes continuously while it is running. If the engine is running lean, …the powertrain control module will sense this from the oxygen sensor's signal and increase the air/fuel mixture to the engine. Conversely, just the opposite occurs when the engine begins to run rich. On OBDII-equipped vehicles, the sensors are also used to help determine the efficiency of the catalytic converter. The powertrain control module does this by comparing the signal of the sensor located at the inlet of the catalytic converter with the signal of the sensor located at the outlet of the converter. (MORE)
Engine light on code P0420 catalyst effientcy below threshold changed both 02 sensors cause and how to correct car still runs great and no smell?
Answer . This engine code can be triggered by any one of the following: 1.) The catalyst in the catalytic converter is cracked, clogged, or otherwise damaged. 2.) The secondary O2 sensor is malfunctioning. 3.) There is an exhaust leak. 4.) The computer unit is faulty.
it has to be reset if you disconnect the battery for a few minutes should do it
O2 sensors are located on the exhaust system in todays vehicles, they monitor the oxygen levels in the engines exhaust gases. They send that information to the vehicles computer which inturn regulates the engine's fuel system for a clean burn.
What does 02 Sensor circuit Low Volts bank 2 sensor 2 Mean. Already replaced both 02 sensors in 1999 Z28 Camaro. It is error P0157 on the OBII scanner.?
go to, http://www.camaroz28.com/ , on this site you can find out what the error is. they have a good message board where you can talk others with the same problems.
There are many reasons why a check engine light could come onfollowing a timing belt change. When the check engine light comeson there is a code stored in the computer to tell you why the lightcame on. Most auto parts stores will read the code for free.
02 mountaineer- service engine soon light on- getting 401 and 125 codes have replaced the egr valve egr solenoid and temp sensor service light on again within 2 miles why?
try changing the d.p.f.e. cost about $35,i just replaced one on a 2003 mercury mountaineer.
Can anyone help I need to change my starter in my 02 camaro and cant find it. Is it on the engine or transmission?
It is on the passenger side. If you cant find it how can you change it.
If you changed the right one the one before the converter then it should go off but you must erase it from the OBD yourself using a scan tool or taking it to somebody.
Infiniti QX4 O2 sensors---HELP How do you get the check engine light off.replaced sensors -still on 3 trips to mechanic...have had 2 replaced...runs fine..light still on.?
Take it to an Infiniti or Nissan dealer, they will rape you but should be able to get the problem taken care of. Take it to an Infiniti or Nissan dealer, they will rape you but should be able to get the problem taken care of
No. Most factory sensors are built by outside resources. you can buy any direct fit sensor from bosch, ngk, aisin etc.
1997 Mercury Mountaineer - Ford Explorer. Why does the check engine lite keeps coming on - have had 02 sensors and CAT changed but that didn't fix it.?
Similar problem. Tyrned out it was a hose that was slightly dry rotted and the cracks were keeping the system from establishing a good vacuum. Check for any hoses that might be cracked.
Check engine light is still on after replacing the ox sensor which is what the code read when checked should you replace the rear one or the cat con?
If a person has performed the steps to reset the computer after theO2 Sensor is fixed and the light is still on, then recheck thecomputer code for a new problem. If the warning light has not beenreset, unhook the battery for about 10 minutes and then hook itback up. The light should be off when the …key is turned. (MORE)
It requires a scanner as the new computors keep history codes. Removing a battery cable will NOT do it.
It depends on the year, make, model, and engine. They are always in the exhaust stream near the engine.
You need to read the code(s) set to begin to make repairs. Depending on what model and year your vehicle is you probably have more than one O2 sensor. Many auto parts stores will read your codes for free in hopes you will purchase the parts from them to correct your problem.
oxygen sensor ( in the exhaust , the sensors closest to the engine are used to " sense " the amount of oxygen in the exhaust to send a signal to the PCM so the air / fuel mixture for the engine is adjusted under various conditions )
Yes, there are 4 O2 sensors on the newer 3.9L engines. Have fun paying for those. I would recommend the OE (original equipment) type sensors, not the universal ones. The wire splicing is easy, but it sometimes goes bad. Might as well fix it right.. As a general rule if there are 2 catalytic convert…ers there are 4 sensors. (MORE)
The sole function of the 'check engine' light is not totally restricted to malfunctioning oxygen sensors. There are a myriad of things that can cause this warning indicator to illuminate on the dashboard. When it come on, there is a code number then stored in the computer's memory - requires a speci…al tool to read that code number and then interpret that number into plain language we can understand. The tool is quite expensive ... not what the ordinary DIY home garage wanna be mechanic would buy to use maybe once or twice a year. Places like Autozone will read the codes for a nominal fee. At least, that done, you will know what the problem really is. Shooting from the hip in troubleshooting car problems is not the best solution. Chances are, those oxygen sensors were okay and didn't even need to be replaced. Get it checked out to find out the real problems. (MORE)
A P0158 code shows 02 sensor High voltage Bank 2 Sensor 2 on a 2002 Dodge Intrepid where is it located?
looking at the car it's on the left side, past the cat, under the air filter box
Bank 1 is the same side as cylinder #1. Sensor 2 is after the catalytic converter.
Unplug the battery of the car and let the power that is in the system drain. You can do this by wither letting the car sit overnight or hitting the breaks once the battery is unpluged. Another method is to remove the main fuse and let the car drain its power. http://www.clublexus.com/forums/per…formance/35057-ecu-reset-remove-fuse-or-disconnect-battery.html (MORE)
my mercury 2000 sable is running lean--how expensive to fix? . Replacing the O2 sensor? . The way I read this, is the questioner want to purchase a new 02 sensor because the vehicle is running lean(??) The sensor is not the CAUSE of the lean condition - it is only the sensor which reported …the reading that the computer then has interpreted to be a lean condition. Something else is happening that is generating the scan codes - likely some type of vacuum leak - air getting into the system that the computer is unaware of. It's kinda like buying a new thermometer when it reports you have a fever, in order to get rid of the fever. Btw, the car's diagnostic trouble codes (DTC) will be much more specific when the 02 sensor really is failing. See "Related Questions" below for more (MORE)
Should the check engine light come on again after the 02 sensor and cam shaft sensores have been replaced in a 1998 ford explorer?
No ,the check engine light indicates a trouble code. Have the truck scanned, it is the fastest way to diagnose the problem.
you have to get a o2 sensor socket at any auto parts place, the best way to change is run car for a few minutes, then shut off, jack up car .the sensors screw out! be carefull that you do not harm the sensor wire. or you can make a socket from a deep well socket. just cut about a half inch slot one …1 side of socket. for wire!! (MORE)
You get a too lean or rich fuel code on 1998 Windstar and recommendation to change the heated 02 sensor bank 2 sensor 1 so how do I change it and where is it located?
Why blame the sensor? The sensor is reporting the data - so people tell you to replace the sensor instead of finding out WHY the data is triggering the codes? Do people buy new thermometers every time one reports they have a fever? There are codes that very specifically address a sensor failure. …Too lean and Too rich are obviously very different and you're not ever going to get both at one time. More specifics regarding the actual codes being triggered and then much more research. Your O2 sensor will be located either in the exhaust manifold (I think that's the most likely spot) after the collector pipe, or it will be in the exhaust pipe prior to the catalytic converter. You should be able to get an open end wrench on it and it will unscrew. If it's in the manifold, there might be some heat shielding in the way that you'll have to remove. They make special sockets that have a channel for the wires to fit into, which would make removal much easier (no need to worry about heat shielding). There is likely a second O2 sensor after your catalytic converter, but (somebody correct me if I'm wrong), the O2 sensor that determines air to fuel ratio is the one that is before the cat, and that would be the one giving you the error. (MORE)
Bank one is the side of the engine with cylinder #1. Sensor two is after the catalytic converter.
The check engine light (service engine soon) comes on and stays on when a problem is detected by the self diagnosis system of your vehicle. Generally, the problem is in the emissions or something that is affecting the effectiveness of the emissions, but other causes can trigger the light to come on,… too. To determine the cause, the vehicle will need to be taken to AutoZone or a shop that has an OBD2 scanner, or for 1995 and earlier models, an OBD1 scanner, While a scanner will not give you the magic answer, it will give you a code that narrows down the problem area. (MORE)
Check engine light keeps coming on in 98 VW Jetta O2 sensor reading replaced 02 sensor still coming on what to do?
You need to have the ECU scanned with an OBD2 scanner and retrieve the code that has been set. The code will tell you what part of the emissions system is being effected. This will help you diagnose the problem. Or you can keep spending money throwing parts at the problem until you may or may not fi…nd the faulty part. (MORE)