New Problem... Backfiring
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Just going by the analog gauges inside the car... I know they are a bit off... usually by 5 degrees or so from the digital... but you know I didn't bother checking that... maybe I should... but like I said... based on the analog gauge... about those readings and when it goes below the 185 mark on the gauge... it seems to run fine again.... it's killing me.
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Rgr... I'll check digital... but for an air pocket... this been going on too long I think... it really seems like a sensor because it is spot on all the time about the same analog gauge readings when it happens... basically open/close loop circuit kicking on/off and then it starts hating me. Yeah I'll run it in a bit again and see what it does and report back at the temps it hits on the digital gauge... I'll run the AC to get it up there faster so I don't have to make laps on the highway so much... it is finally cooler in Houston today and of course made me think everything was good until it hit those magic temp numbers... lol
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***Update*** 8/29
Anyway I ran it today for 35 min or so driving around the city doing things... the check engine light for the code 43 went on and off randomly whenever, but still on most of the time. No stumbles until about the end of my drive... it always seems to die when I'm making a right hand turn slowly... but I didn't have any other problems until then and no more happened after that before I got home. Temp digital gauge stayed below 190.... 189 was the highest it got to today, but I wasn't running the A/C either. So something is still causing it to die after heating up, but not stumble at those temps... next test is to run it with A/C on and get it above 190 and see where the stumbles really start.
Anyway I ran it today for 35 min or so driving around the city doing things... the check engine light for the code 43 went on and off randomly whenever, but still on most of the time. No stumbles until about the end of my drive... it always seems to die when I'm making a right hand turn slowly... but I didn't have any other problems until then and no more happened after that before I got home. Temp digital gauge stayed below 190.... 189 was the highest it got to today, but I wasn't running the A/C either. So something is still causing it to die after heating up, but not stumble at those temps... next test is to run it with A/C on and get it above 190 and see where the stumbles really start.
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Get a freezer pack and when it stumbles put it on your puter or icm and see if it helps coils can fail when hot and going hope it is not your opti.
Did you get the air out?
Did you get the air out?
Last edited by antfarmer2; Aug 29, 2015 at 08:22 AM.
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The air thing... haven't checked yet... will do that when I got time.
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and your temp sender on the water pump can do some strange things.New parts can go or be bad!!!!!
There are two bleeders on your car.
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*UPDATE* 9/15/2015
Well We checked the bleeds... it was good Ant... temp sender was good on test runs... I changed the fuel pump, fuel filter, and EGR Valve... that seems to have fixed the studdering and loss of power issues that were randomly happening... I'm guessing it was the EGR Valve gone bad... mechanic said when they did a vacuum test on the EGR Valve... it wasn't holding pressure. Anyway... everything seems to be fixed except the fact that now that everything is fixed... the stupid Service Engine Soon light still comes on and goes off randomly at times... still giving me the Code 43 for Knock Sensors... LOL... that problem seems be have been here the last 2 years now. It was gone when I had the bad MSD optispark in the car... and when I replaced it with the good ACDelco one... and the car ran better without backfires... that damn light came back. Gremlins.
Well We checked the bleeds... it was good Ant... temp sender was good on test runs... I changed the fuel pump, fuel filter, and EGR Valve... that seems to have fixed the studdering and loss of power issues that were randomly happening... I'm guessing it was the EGR Valve gone bad... mechanic said when they did a vacuum test on the EGR Valve... it wasn't holding pressure. Anyway... everything seems to be fixed except the fact that now that everything is fixed... the stupid Service Engine Soon light still comes on and goes off randomly at times... still giving me the Code 43 for Knock Sensors... LOL... that problem seems be have been here the last 2 years now. It was gone when I had the bad MSD optispark in the car... and when I replaced it with the good ACDelco one... and the car ran better without backfires... that damn light came back. Gremlins.
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From: N. Babylon NY
*UPDATE* 9/15/2015
Well We checked the bleeds... it was good Ant... temp sender was good on test runs... I changed the fuel pump, fuel filter, and EGR Valve... that seems to have fixed the studdering and loss of power issues that were randomly happening... I'm guessing it was the EGR Valve gone bad... mechanic said when they did a vacuum test on the EGR Valve... it wasn't holding pressure. Anyway... everything seems to be fixed except the fact that now that everything is fixed... the stupid Service Engine Soon light still comes on and goes off randomly at times... still giving me the Code 43 for Knock Sensors... LOL... that problem seems be have been here the last 2 years now. It was gone when I had the bad MSD optispark in the car... and when I replaced it with the good ACDelco one... and the car ran better without backfires... that damn light came back. Gremlins.
Well We checked the bleeds... it was good Ant... temp sender was good on test runs... I changed the fuel pump, fuel filter, and EGR Valve... that seems to have fixed the studdering and loss of power issues that were randomly happening... I'm guessing it was the EGR Valve gone bad... mechanic said when they did a vacuum test on the EGR Valve... it wasn't holding pressure. Anyway... everything seems to be fixed except the fact that now that everything is fixed... the stupid Service Engine Soon light still comes on and goes off randomly at times... still giving me the Code 43 for Knock Sensors... LOL... that problem seems be have been here the last 2 years now. It was gone when I had the bad MSD optispark in the car... and when I replaced it with the good ACDelco one... and the car ran better without backfires... that damn light came back. Gremlins.
Last edited by STEVEN13; Sep 15, 2015 at 08:25 AM.
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Okay-So now trace your code 43 Knock Sensor problem. If you have the FSM it has a flow chart and is simple to follow. I had this problem on my 1992 and in my case was 1 bad knock sensor. I changed both with the factory A/C brand. No code 43 since (that was 10 years ago).
do them both they are cheap enough and will get a proper flush. tourqe is impotant on them 14 lbs if I remember right
just pinch the connectors with your fingers to release
Last edited by antfarmer2; Sep 15, 2015 at 11:35 AM.
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Cats are new... or they were at least... they suffered about a month or two of the fuel flooding the FPR was causing before I got it replaced... don't know how good they are now. Knock sensors were already new as well but at the 14lb torque limit... have no idea. My guess is probably exhaust... it's been needing a new exhaust completely redone for a while... but sensors are cheap... might as well re-check those.
Last edited by 94LT4Corvette; Sep 15, 2015 at 10:33 PM.
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Cats are new... or they were at least... they suffered about a month or two of the fuel flooding the FPR was causing before I got it replaced... don't know how good they are now. Knock sensors were already new as well but at the 14lb torque limit... have no idea. My guess is probably exhaust... it's been needing a new exhaust completely redone for a while... but sensors are cheap... might as well re-check those.
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Okay nah... he didn't grease them... they are in as normal. Question though because I did say this... don't know if you had caught it or not... that error code was basically gone while I had the MSD Optispark in... although that Opti ran like crap and caused the backfiring that would later make the code come on, but it mainly never happened... and now that the new AC Delco Opti is in and running great... that code just stays on constantly just about. So my thing is... if the code didn't come on before with the bad Opti... what could cause it to come on with a good opti? Something doesn't seem right... like maybe loose wires or something that was moved around again when we changed the opti.
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Okay nah... he didn't grease them... they are in as normal. Question though because I did say this... don't know if you had caught it or not... that error code was basically gone while I had the MSD Optispark in... although that Opti ran like crap and caused the backfiring that would later make the code come on, but it mainly never happened... and now that the new AC Delco Opti is in and running great... that code just stays on constantly just about. So my thing is... if the code didn't come on before with the bad Opti... what could cause it to come on with a good opti? Something doesn't seem right... like maybe loose wires or something that was moved around again when we changed the opti.
the knock sensors are not by the opti. try clearing the codes and see if it comes back might have a bad one or was torourqe wrong.
check the connection and make sure they are clean. just pinch it with your fingers. look at the wires and make sure they are not burned or shorted.