Codes 41 and 52
06-18-2013, 02:26 PM
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Codes 41 and 52
So i was driving home today and stopped at a stop sign. When i started rolling again my check engine light came on.
I believe it is a code 41 and a code 52 and then the 25 that i thought i had fixed.
I had the 25 previously buy plugging the TPS in fixed that for 3 or four days and now i have these three codes.
Only issue i know of that may have an effect on this is that my battery ground and my block ground are bad, but i won't have a chance to work on the truck for a week or so due to work and such, but i won't be driving it for the same amount of time after Saturday for the same reasons so problems won't be getting worse in between(hopefully).
Does anyone have any ideas as to the cause of these errors?
Thanks,
Speed
I believe it is a code 41 and a code 52 and then the 25 that i thought i had fixed.
I had the 25 previously buy plugging the TPS in fixed that for 3 or four days and now i have these three codes.
Only issue i know of that may have an effect on this is that my battery ground and my block ground are bad, but i won't have a chance to work on the truck for a week or so due to work and such, but i won't be driving it for the same amount of time after Saturday for the same reasons so problems won't be getting worse in between(hopefully).
Does anyone have any ideas as to the cause of these errors?
Thanks,
Speed
06-19-2013, 08:40 AM
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FSM says:
Soo... As i have already had issues with the TPS (intermittent code 25) i assume that means i need to check and possible replace the wiring for both sensors?
IS there a straightforward way to test these circuit? If not what would it take to replace them?
Error 41: Open or short detected in throttle position sensor signal (VTA) for 500 msec. or more.
Error 52: With engine speed 2,000 rpm or more signal from knock sensor is not input to ECM for 25 revolution. (KNK)
Error 52: With engine speed 2,000 rpm or more signal from knock sensor is not input to ECM for 25 revolution. (KNK)
IS there a straightforward way to test these circuit? If not what would it take to replace them?
06-19-2013, 08:51 AM
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If I understand correctly, you had the TPS unplugged before you had this issue?
Sounds like your TPS is bad or terribly out of adjustment. Could cause the engine to run lean, hence the code 25 and 52 (lean condition and knocking). Try adjusting it per the Factory Service Manual: http://personal.utulsa.edu/~nathan-b...34throttle.pdf. You'll need a feeler gauge and some patience to do it right. If you end up needing a new one, you'll need to repeat the adjustment, just slapping it on might bring back the same issues.
If you do fix/adjust/replace the TPS and you still have issues, let us know. My first premonition is that all three are related to the TPS.
Sounds like your TPS is bad or terribly out of adjustment. Could cause the engine to run lean, hence the code 25 and 52 (lean condition and knocking). Try adjusting it per the Factory Service Manual: http://personal.utulsa.edu/~nathan-b...34throttle.pdf. You'll need a feeler gauge and some patience to do it right. If you end up needing a new one, you'll need to repeat the adjustment, just slapping it on might bring back the same issues.
If you do fix/adjust/replace the TPS and you still have issues, let us know. My first premonition is that all three are related to the TPS.
06-19-2013, 09:02 AM
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If I understand correctly, you had the TPS unplugged before you had this issue?
Sounds like your TPS is bad or terribly out of adjustment. Could cause the engine to run lean, hence the code 25 and 52 (lean condition and knocking). Try adjusting it per the Factory Service Manual: http://personal.utulsa.edu/~nathan-b...34throttle.pdf. You'll need a feeler gauge and some patience to do it right. If you end up needing a new one, you'll need to repeat the adjustment, just slapping it on might bring back the same issues.
If you do fix/adjust/replace the TPS and you still have issues, let us know. My first premonition is that all three are related to the TPS.
Sounds like your TPS is bad or terribly out of adjustment. Could cause the engine to run lean, hence the code 25 and 52 (lean condition and knocking). Try adjusting it per the Factory Service Manual: http://personal.utulsa.edu/~nathan-b...34throttle.pdf. You'll need a feeler gauge and some patience to do it right. If you end up needing a new one, you'll need to repeat the adjustment, just slapping it on might bring back the same issues.
If you do fix/adjust/replace the TPS and you still have issues, let us know. My first premonition is that all three are related to the TPS.
You are correct the PO had left the TPS unplugged and when i noticed it i plugged it back in. Yes it could cause the engine to run lean and to knock, but #52 does not indicate knocking it indicates problem in the knock sensor circuit. If i can get a hold of a feeler gauge i may have a go at that adjustment but i'm not sure that will fix my issues.
I know something is wrong with the TPS or its wiring because my idle has become a lot rougher 1200 rpms vs 750 and i am lacking power during acceleration. Problem is i don't know what to do with this info? Do i check the wiring, if so how? Or do i replace the sensor?
And how is related to the knock sensor circuit? Its seems rather coincidental that they would both through an error at the same time.
06-19-2013, 09:21 AM
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Thanks for your reply, i am going crazy here.
You are correct the PO had left the TPS unplugged and when i noticed it i plugged it back in. Yes it could cause the engine to run lean and to knock, but #52 does not indicate knocking it indicates problem in the knock sensor circuit. If i can get a hold of a feeler gauge i may have a go at that adjustment but i'm not sure that will fix my issues.
I know something is wrong with the TPS or its wiring because my idle has become a lot rougher 1200 rpms vs 750 and i am lacking power during acceleration. Problem is i don't know what to do with this info? Do i check the wiring, if so how? Or do i replace the sensor?
And how is related to the knock sensor circuit? Its seems rather coincidental that they would both through an error at the same time.
You are correct the PO had left the TPS unplugged and when i noticed it i plugged it back in. Yes it could cause the engine to run lean and to knock, but #52 does not indicate knocking it indicates problem in the knock sensor circuit. If i can get a hold of a feeler gauge i may have a go at that adjustment but i'm not sure that will fix my issues.
I know something is wrong with the TPS or its wiring because my idle has become a lot rougher 1200 rpms vs 750 and i am lacking power during acceleration. Problem is i don't know what to do with this info? Do i check the wiring, if so how? Or do i replace the sensor?
And how is related to the knock sensor circuit? Its seems rather coincidental that they would both through an error at the same time.
Basically, you are measuring what signal the TPS should be putting out when it's idling and when you press on the gas. If it shows readings outside of this range, you'll need to turn the TPS on the throttle body ever so slightly and secure. This is easiest with two people, since one can measure with the multi-meter and the other can slowly rotate the TPS and secure when needed but can be done with one person.
Don't have a multi-meter or a feeler gauge? Both can be picked up for $10 total at Harbor Freight, or under $20 at an auto store. Those TPS can run upwards of $90 so it's better to check yours than to just buy a new one.
I would not worry about the 52. I had it come up once for me when I had a bad distributor and my engine was knocking bad. Replaced distributor, never had the knocking or code 52 ever again.
06-19-2013, 01:09 PM
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Ok, I'll try and explain this as best I can. You'll need a multi-meter or ohmeter to measure resistance (ohms) on the different prongs on the TPS connector. Most measurements are in kilo-ohms so when it says .47kohms, it means 470 ohms. Also, Infinity means no connectivity, so it might show "1" on your display. Follow the specifications on the service manual link I provided (in section 2) to compare. You'll need to ensure each measurement is within this range. The TPS must be on the throttle body to do this and you "adjust" the TPS by turning it every so slightly left or right and re-measuring the resistance. To create the gap, place the feeler gauge in between the lever and the screw at the recommended thickness (.57 mm and .85mm) and measure.
Basically, you are measuring what signal the TPS should be putting out when it's idling and when you press on the gas. If it shows readings outside of this range, you'll need to turn the TPS on the throttle body ever so slightly and secure. This is easiest with two people, since one can measure with the multi-meter and the other can slowly rotate the TPS and secure when needed but can be done with one person.
Don't have a multi-meter or a feeler gauge? Both can be picked up for $10 total at Harbor Freight, or under $20 at an auto store. Those TPS can run upwards of $90 so it's better to check yours than to just buy a new one.
I would not worry about the 52. I had it come up once for me when I had a bad distributor and my engine was knocking bad. Replaced distributor, never had the knocking or code 52 ever again.
Basically, you are measuring what signal the TPS should be putting out when it's idling and when you press on the gas. If it shows readings outside of this range, you'll need to turn the TPS on the throttle body ever so slightly and secure. This is easiest with two people, since one can measure with the multi-meter and the other can slowly rotate the TPS and secure when needed but can be done with one person.
Don't have a multi-meter or a feeler gauge? Both can be picked up for $10 total at Harbor Freight, or under $20 at an auto store. Those TPS can run upwards of $90 so it's better to check yours than to just buy a new one.
I would not worry about the 52. I had it come up once for me when I had a bad distributor and my engine was knocking bad. Replaced distributor, never had the knocking or code 52 ever again.
I will start with this, but i rather beg to differ on leaving the #52. According to the FSM when that circuit is found to be bad the ECU retards the timing, just to be on the safe side so to speak, so i would rather get it fixed at some point. But for now i will focus on the tps. Hopefully i can get to it before i take off for the week.
06-23-2013, 08:47 AM
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SpeedCrazy is right about code 52. It has nothing to do with whether the engine is knocking; it means that the ECU "hasn't heard from" the knock sensor in a while. Usually a wiring problem (the sensor itself is very tough), so it is certainly possible to be intermittent.
But as SC says, if you have a real code 52 the ECU substantially retards the timing in order to save the engine. Meaning: it will drive like crap. You gotta get it fixed.
While setting the idle contacts on the TPS is important, if it is actually causing a code 25 the problem is in the rheostat part. Check that the VTA-E2 resistance changes smoothly as you move the throttle; if there is a dead spot in the rheostat it won't work.
Last, if you have an automatic transmission, you're in luck! The transmission uses the same TPS signal to determine throttle position, and you can do an end-to-end test of the TPS right from the diagnostic connector. http://personal.utulsa.edu/~nathan-b...34electron.pdf
But as SC says, if you have a real code 52 the ECU substantially retards the timing in order to save the engine. Meaning: it will drive like crap. You gotta get it fixed.
While setting the idle contacts on the TPS is important, if it is actually causing a code 25 the problem is in the rheostat part. Check that the VTA-E2 resistance changes smoothly as you move the throttle; if there is a dead spot in the rheostat it won't work.
Last, if you have an automatic transmission, you're in luck! The transmission uses the same TPS signal to determine throttle position, and you can do an end-to-end test of the TPS right from the diagnostic connector. http://personal.utulsa.edu/~nathan-b...34electron.pdf
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06-29-2013, 04:00 PM
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SpeedCrazy is right about code 52. It has nothing to do with whether the engine is knocking; it means that the ECU "hasn't heard from" the knock sensor in a while. Usually a wiring problem (the sensor itself is very tough), so it is certainly possible to be intermittent.
But as SC says, if you have a real code 52 the ECU substantially retards the timing in order to save the engine. Meaning: it will drive like crap. You gotta get it fixed.
While setting the idle contacts on the TPS is important, if it is actually causing a code 25 the problem is in the rheostat part. Check that the VTA-E2 resistance changes smoothly as you move the throttle; if there is a dead spot in the rheostat it won't work.
Last, if you have an automatic transmission, you're in luck! The transmission uses the same TPS signal to determine throttle position, and you can do an end-to-end test of the TPS right from the diagnostic connector. http://personal.utulsa.edu/~nathan-b...34electron.pdf
But as SC says, if you have a real code 52 the ECU substantially retards the timing in order to save the engine. Meaning: it will drive like crap. You gotta get it fixed.
While setting the idle contacts on the TPS is important, if it is actually causing a code 25 the problem is in the rheostat part. Check that the VTA-E2 resistance changes smoothly as you move the throttle; if there is a dead spot in the rheostat it won't work.
Last, if you have an automatic transmission, you're in luck! The transmission uses the same TPS signal to determine throttle position, and you can do an end-to-end test of the TPS right from the diagnostic connector. http://personal.utulsa.edu/~nathan-b...34electron.pdf
It does drive horribly. Just got back from my trip and used it to run into town, while i was at it i put it through its paces to make sure of what i was experiencing before i got back on here.
My findings:
- Idle fluctuates ridiculously. When i started her up it idled at about 1500, by the time i got into town it was idling at roughly 600. And on the way home it bounced through that whole range.
- Acceleration is intermittently sluggish. At times i could accelerate fine, but proved to be lacking before long. Flooring the gas pedal while accelerating through intersections resulted in jerking and surging, and accelerating to pass lacked any oomph what-so-ever.
- At cruising speed i was struggling more than normal on hills.
07-04-2013, 11:13 AM
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Well i have some good news, and some bad news.
Bad news first, i did not learn how to test all this stuff myself.
Good news, the problem is fixed.
How you ask? I replaced all my grounds and battery cables and even after 3 days of driving the problems have not made an appearance and the cel has stayed off.
So to anyone who may read this thread in the future while dealing with a similar problem CHECK YOUR GROUNDS!!!
Bad news first, i did not learn how to test all this stuff myself.
Good news, the problem is fixed.
How you ask? I replaced all my grounds and battery cables and even after 3 days of driving the problems have not made an appearance and the cel has stayed off.
So to anyone who may read this thread in the future while dealing with a similar problem CHECK YOUR GROUNDS!!!
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