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2G Huge backfire, cutting out

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Wasteland

Proven Member
51
4
Jul 22, 2020
Pioneer, California
Hope someone sees this.

I have a 96GST That idles fine then a minute down the road it starts backfiring out the pipe and tries to shut off and sometimes does. But it will always idle ok. Revs up blow off does it’s job start going down the road plenty of power then starts cutting off then backfires over and over until you turn key on and off. If you wait about five minutes it acts fine again the the same thing?

I have two for spare so I’ll try whatever. Already check the usual. Timing plugs Wired’s vac leaks coils.... pressures. . Please help I am loosing it. Lol


Backfires out the pipe... not lip .... LOL

Not getting any codes forgot that .... duh o codes
 
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Ok so changed the firing order back to what stock is for it to start and runs great little surges at idle but over all reading are were they should be. A/f and the basics.... but .... holding at anything above 3200 rpm and does the same old backfire BS.... so changing over cam sensor still didn’t change anything but still codes cam sensor. P0340 or something like that....
 
sound's a lot like an ECU fuel cut, you will need ECM Link to log it and see why and where it happens, what fuel pump you running? is a majority of the intake parts stock? like the injectors,etc. Are you running a stock 14b or T25 turbo's, whats boost psi sitting at?
Sorry forgot to refresh....
changed fuel pump to another one but yes stock of the majority. Also stock boost Control and stock injectors. Changed most sensors over but just over to newer stock ones.
I’m thinking it’s going back and fourth to open and closed loop. Why it would do that and not give any symptoms is strange. Temp reads like it should air and intake temps read correctly
 
well for something like that it probably won't spit code unless it happens for more than a few seconds but an ECU log will catch it most definitely. The best bet, if you have an extra ECU lying around you, could change ECU out with a different one to see if the same symptoms happen this one's a dousey cause for that p0340 code these are the symptom's

bold/underlined symptoms are your culprit
  • A defective camshaft position sensor
  • Damaged or dirty reluctor ring on the camshaft
  • Defective, corroded, shorted camshaft position sensor circuit wiring
  • Defective, corroded, shorted camshaft position sensor circuit connector
  • A faulty crankshaft position sensor
  • Stretched or misaligned timing components
  • ECM software update needed
  • Faulty ECM
(a bad crankshaft position sensor will cause that engine stall while revving)
mine did that around 4500 rpm while gunning/holding it then it would stall replaced crank sensor and its been fine ever since
 
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well for something like that it probably won't spit code unless it happens for more than a few seconds but an ECU log will catch it most definitely. The best bet, if you have an extra ECU lying around you, could change ECU out with a different one to see if the same symptoms happen this one's a dousey cause for that p0340 code these are the symptom's

bold/underlined symptoms are your culprit
  • A defective camshaft position sensor
  • Damaged or dirty reluctor ring on the camshaft
  • Defective, corroded, shorted camshaft position sensor circuit wiring
  • Defective, corroded, shorted camshaft position sensor circuit connector
  • A faulty crankshaft position sensor
  • Stretched or misaligned timing components
  • ECM software update needed
  • Faulty ECM
(a bad crankshaft position sensor will cause that engine stall while revving)
mine did that around 4500 rpm while gunning/holding it then it would stall replaced crank sensor and its been fine ever since
Unfortunately it was doing it oh teen 96ECMN I changed over to the 99 everything else I already checked into changed out that’s what’s bugging me is I’ve done everything that people are suggesting before I even started this thread so the only thing I’ve done is when ahead and changed over cam sensors and using D 99 cam sensor instead of the older style that’s mounted on the gear nothing changed as of yet. That’s what’s driving me nuts. And I watch data stream and like I mentioned before the open and closed loop is the only abnormal thing. I don’t know what’s causing it to do that.
 
Unfortunately it was doing it oh teen 96ECMN I changed over to the 99 everything else I already checked into changed out that’s what’s bugging me is I’ve done everything that people are suggesting before I even started this thread so the only thing I’ve done is when ahead and changed over cam sensors and using D 99 cam sensor instead of the older style that’s mounted on the gear nothing changed as of yet. That’s what’s driving me nuts. And I watch data stream and like I mentioned before the open and closed loop is the only abnormal thing. I don’t know what’s causing it to do that.
Sorry for all the funky language using voice to text
 
Either ECU fuel cut or a bad crankshaft sensor since it happens after a few high rev's and a hold around 3500rpm, this is one of the main culprits, I lean towards crankshaft sensor

I noticed you said you replaced the CAM sensor or went with a 99 but I do not see you say you replaced the Crank Sensor which would have been done when you Re-timed it, it's the same sensor as the cam sensor just located behind crank sprocket

and go back to the old style cam sensor its a better setup because it doesn't rely on a magnet to tell the ECU when to fire
 
It’s still doing it.....
I had changed cam sensor when I replaced timing belt. And also then changed it over to 99 pick up and it’s still doing same thing.
Change fuel pump and basically as I went along I swapped sensor after sensor cleaned up wiring alt was caked in grease so cleaned that also. Different injectors still stock....
WHAT WOULD BE A GOOD STOCK INJECTOR UPGRADE THAT JUST PLUG AND PLAY???
 
Wanted to say thanks everyone for ideas. Now that I have had the car a bit and have seen the quality of work done to it.... He said he changed cam and crank sensors but I never checked the crank sensor to see if was done correctly or not at all.....
 
change crank sensor if its still doing it and you changed every sensor, since you replaced cam sensor and didn't fix the issue that leaves one viable option your crank sensor
Going to get to that now..... I’ll post results as soon as I have one,,,
 
So far so good has ticking noise maybe flip wheel around maybe but no backfire so far!!!! Thanks for confirming because I didn’t really want to take it apart again but gots to do what ya gots to do LOL
 
Well got an update!!!
I changed crank senor and pick up. Sounds like something making contact due to a new ticking sound. Maybe I put pick up wheel on the wrong way do you rushing but I kinda doubt it. Just came back from taking it out and.....(drum roll) it did it BUT it took awhile and it didn’t code sensor like before but a 0300 which we all know that one. Also still coding Insignificant temperature on fuel status. It’s reading proper temp but that should be simple.
So I’ll fix ticking and inspect sensor and pick up replace if need be. I mean shit what else could it be, right.

Is there a way not to use crank sensor and use cam for both??

Oh yeah also any ideas on a stock injector upgrade? example like 3000gt or 37o Nissan ,,,
 
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Have not had an answer but Kyle was right it’s the crank sensor even though brand new. Issue with it now it’s all back together is that it sounds like it’s hitting, the pick up and plate.... That’s one reason I was asking about a deletion. Maybe an adjustable electric like old school?
Can’t really see exactly why the ticking happens but can’t hear while turning over to start...
This car has strange issues...THATS WHAT HAPPENS WHEN YOU TAKE ON SOMEONE ELSES PROJECTS! !!! everytime...
 
you can run a 1g cam sensor. it will provide the cam and crank signals to the ecu. you can then remove the stock cam and crank sensors

if your running a 96 on a 99 ecu and you swapped injector pin and plug wires, you would need to swap them back to run the 99 cam sensor.

 
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That’s sounds like a great idea. On the 96 I’m running the 98 cam sensor and black ECU so I’m running firing order which was easy enough. Is there a diagram or pics with details?
 
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http://eatsleepdsmmag.com/using-a-97-99-ecu-in-a-95-96-dsm/

http://www.roadraceengineering.com/1gcasin2g.htm

http://www.roadraceengineering.com/1gcasin2g97-99.htm

with a 1g cam sensor and a 99 ecu you want to make sure your firing order is the normal 4 1 2 3
and if you swapped injector plugs or pins they also need to be swapped back to the stock configuration
Being I updated cam sensor to the 99 it’s already set 4123... besides talon and eclipse did other older Mitsubishi have same sensor because 1g getting hard to find?
 
Almost everything for a 1g is rare now days, that 1g cam sensor is like $500 at some auto parts store's around here. its ridiculous, but glad to see it was the crank sensor for the first issue. Now for your other issue's, since it is/was back to working order..... why not go back to stock config for your cam sensor (go back to 99' style, cost of a new one = $70 vs $500 on a 1g) unless there is a specific reason is at hand to have the 1G cam sensor?
 
Almost everything for a 1g is rare now days, that 1g cam sensor is like $500 at some auto parts store's around here. its ridiculous, but glad to see it was the crank sensor for the first issue. Now for your other issue's, since it is/was back to working order..... why not go back to stock config for your cam sensor (go back to 99' style, cost of a new one = $70 vs $500 on a 1g) unless there is a specific reason is at hand to have the 1G cam sensor?
The cam sensor works fine wanting to delete crack sensor. The plate and pick up keep hitting. It looks fine can’t hear it when you turn it over but once it starts you hear it. And as the ticking fades the backfire starts. Just can’t see why it’s hitting. Wish you could just wire it up due it looks almost the same...
 
The cam sensor works fine wanting to delete crack sensor. The plate and pick up keep hitting. It looks fine can’t hear it when you turn it over but once it starts you hear it. And as the ticking fades the backfire starts. Just can’t see why it’s hitting. Wish you could just wire it up due it looks almost the same...
Spacing is off some how but if anyone want to do a trade for almost anything 95-96 I would consider a trade... I do have 3GS Spyder and 2 GST Spyder
 
Spacing is off some how but if anyone want to do a trade for almost anything 95-96 I would consider a trade... I do have 3GS Spyder and 2 GST Spyder
Spacing is off some how but if anyone want to do a trade for almost anything 95-96 I would consider a trade... I do have 3GS Spyder and 2 GST Spyder
crack sensor LOLoLOL
 
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