Okay I recently Just got the soup running again and I've been javing some idle issues so after a few weeks I've solved it for the most part but I'm still getting intermittent popping not exactly backfiring almost like it's missing but not consistently. Now I've gotten the idle under controll for the most part. But now when I go to test drive it it starts to buck and jerk but only at low rpms and then is fine over 2500 rpm mostly. Now after that I start to get backfiring out of nowhere but no idle bogging and no rpm searching. And I have checked codes and I have come up with no codes! I'm dumbfounded and I reset timing everytime I go to run it because I am having idle issues. Any help is appreciated thanks!
Still more problems! Backfire only after driving
- Thread starter mizuboi
- Start date
I would try checking the fuel pressure. Take your plugs out and see if they look white looking. If they do, that is a sign you are running lean.
Im having an issue like yours and like the one in the thread listed below. I dont know if you had your CPS out or not but it could be off a tooth. I believe mine is so Im going to recheck going by sawbladez post.
http://www.supramania.com/forums/showthread.php?120652-Ok-having-a-few-issues.-Jerking-rough-idle..
http://www.supramania.com/forums/showthread.php?120652-Ok-having-a-few-issues.-Jerking-rough-idle..
i could have sworn i put the cps in right but ehh heck i'm stumped so i'll most definitely go back and do it again honestly it can't hurt and i've removed all that stuff a million times haha so it shouldn't take more than 15 minutes to re do it ahaha and thanks man i'll definitely post what happened!
okay in the process of redoing my cps i somehow managed to rip a wire out of my water temp sensor and i'm getting code 22 witch i believe to be the water temp sensor... anyways can this cause backfiring? like is it possible that i'm always in cold start fuel mixture? i say this because i looked at my wires and they looked really weak at the site of being snapped. because i just re did my cps and it is set to 10deg with diagnostics jumped and about 12-13 when not jumped. it is idling a little rough the engine shakes quite a bit but only really starts to backfire when engine gets to operating temperatures. and the intermittent miss went away and i hope for good! but uppon going out for a drive it still jerks so i think my clutch might be slipping? please guys i need help with this its driving me crazy! haha
ohh also when i turn on the head lights or the ac the rpms drop really low to like 500 so yea! gosh i just seem to get more and more problems!
ohh also when i turn on the head lights or the ac the rpms drop really low to like 500 so yea! gosh i just seem to get more and more problems!
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A coolent temp sensor not being connected would cause this problem. Whats happening is the ECU is staying in warmup mode which is adding a lot more fuel then the engine needs when it is warmed up. Cut out the old crap wire and install new.
Also people a backfire can be caused by a lean or rich condition.
Also people a backfire can be caused by a lean or rich condition.
gennro;1559886 said:
now this is the type of answer i was looking for thanks! and i will be adjusting my tps just in case and i know the backfire is cause by either lean or rich but i am not really fully sure what is causing it but i'll let you guys know when i fix the code 22
gennro;1559886 said:
I get backfires with out problems and usually its a rich condition.
But yes a water temp sensor will cause problems but it depends which one, which in his case is the one for his ecu since its throwing a code, but this was happening before the water temp sensor code but it could be the wiring altogether.
okay fixed the code 22 put in new coil pack and wires and new ground and different ecu and checked and re aligned tps and re adjusted cps and reset timing and i'm still backfiring!(but really only after getting up to operating temps and driving it! it stutters pretty bad under 2k rpm. seriously i don't know! and i'm still getting an intermittent miss i hear it and the rpm drop about 50 rpm every time it misses then goes back up. i'm stumped.
I get the same kind of issue as you and im still chasing it down but its more intermittent. Sometimes it runs perfect sometimes it misses. When I put in new plugs and gapped them to .028" it helped ALOT. Try using the copper tips instead of the fine wire platinums if you havent already.
@chris i think i might need to do that because i'm pretty sure my plugs are fouled after all the horribly rich running and initial oil burning because i know my #1 plug is pretty bad looking and i just replaced them last month with iridiums
but here is what i did.
i put on the Lexus maf and it runs amazing now!... well sorta its super sluggish under 2k rpm and it backfires now only when decelerating. i think it is because i have my hks bov venting to atm but i only have it that way because my original bypass valve is not working! i'd rather have it vent to the atm than have flutter and kill the turbo faster. but what do you guys think? and the timing is nice it searches slightly for rpms but not alot and idles at around 800
summary
no backfire at idle just a deceleration
put in Lexus maf and it idles pretty smooth now
but what do you guys and gals think of the sluggish low rpm driving and backfiring at deceleration?
but here is what i did.
i put on the Lexus maf and it runs amazing now!... well sorta its super sluggish under 2k rpm and it backfires now only when decelerating. i think it is because i have my hks bov venting to atm but i only have it that way because my original bypass valve is not working! i'd rather have it vent to the atm than have flutter and kill the turbo faster. but what do you guys think? and the timing is nice it searches slightly for rpms but not alot and idles at around 800
summary
no backfire at idle just a deceleration
put in Lexus maf and it idles pretty smooth now
but what do you guys and gals think of the sluggish low rpm driving and backfiring at deceleration?
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=20
Is the ign timing set to 10* btdc?
Is the ign timing set to 10* btdc?
i'm pretty sure but i'll check tomorrow that the timing is correct again and i disconected my cold start injector well.. just the clip but i don't think i'll need it since i live in socal. i'm not getting any codes and i may need a new 02 sensor but i doubt it