Oh yea, and:
The car idles at 1000RPM, moving between 1500 and 1000 constantly
The car idles at 1000RPM, moving between 1500 and 1000 constantly
2003 Eclipse Misfire
YEAR: 2003
SUBMODEL: RS
TRANSMISSION: Automatic
MILES: +-150.000
PROBLEM: Hello everyone. I've stumbled across a P0300 (Multiple Misfires), but i honestly have no clue where to look. It's the only code showing. There's no Check Engine light on either.
Basically What happens is when i turn on the car, it mostly instantly stops at first try, second try it starts, pruttles and vibrates intensely. Sometimes also some squeeky noises from the exhaust.
When i accelerate above 2000RPM, it sounds (semi)normal, still pruttles but not as bad as idle. The car stutters in gear or reverse, also gone if accelerating.
To this point, since it started, we've replaced the spark plugs, coils, wires and the O2 sensor in the exhaust manifold, with no luck. The cilinders are clean, no oil or anything, no fuel laying around, nothing. Car is also not leaking.
Anyone have any idea on what i could try next? Or help me in any other way? I could post a video of how it looks/sounds of requested.
Thanks in advance!
SUBMODEL: RS
TRANSMISSION: Automatic
MILES: +-150.000
PROBLEM: Hello everyone. I've stumbled across a P0300 (Multiple Misfires), but i honestly have no clue where to look. It's the only code showing. There's no Check Engine light on either.
Basically What happens is when i turn on the car, it mostly instantly stops at first try, second try it starts, pruttles and vibrates intensely. Sometimes also some squeeky noises from the exhaust.
When i accelerate above 2000RPM, it sounds (semi)normal, still pruttles but not as bad as idle. The car stutters in gear or reverse, also gone if accelerating.
To this point, since it started, we've replaced the spark plugs, coils, wires and the O2 sensor in the exhaust manifold, with no luck. The cilinders are clean, no oil or anything, no fuel laying around, nothing. Car is also not leaking.
Anyone have any idea on what i could try next? Or help me in any other way? I could post a video of how it looks/sounds of requested.
Thanks in advance!
1 - 7 of 7 Posts
P0300 is just a symptom, and isn't specific enough to help much with your troubleshooting.
Constantly pulsing idle may be from the IAC, but I'd test it first and not jump to replacing it. There's a test procedure in the factory service manual at tearstone.com section 13B, if you have a multitester. Another way to check the IAC is to unplug the MAF. When you unplug the MAF, the ECM sets the IAC to a default position and freezes it there. So if the idle hunting stops when you unplug the MAF, it may be that the IAC is the problem.
For your other symptoms, I'd check for vacuum leaks next. You can't just look at the engine and expect to find leaks. Find a way to keep the engine running, and spray starting fluid or similar around your intake tubing, throttle body, intake manifold, and vacuum lines. It's common for the intake manifold plenum to crack where it attaches to the throttle body which lets in a lot of unmetered air, so that's worth checking first.
Constantly pulsing idle may be from the IAC, but I'd test it first and not jump to replacing it. There's a test procedure in the factory service manual at tearstone.com section 13B, if you have a multitester. Another way to check the IAC is to unplug the MAF. When you unplug the MAF, the ECM sets the IAC to a default position and freezes it there. So if the idle hunting stops when you unplug the MAF, it may be that the IAC is the problem.
For your other symptoms, I'd check for vacuum leaks next. You can't just look at the engine and expect to find leaks. Find a way to keep the engine running, and spray starting fluid or similar around your intake tubing, throttle body, intake manifold, and vacuum lines. It's common for the intake manifold plenum to crack where it attaches to the throttle body which lets in a lot of unmetered air, so that's worth checking first.
We've tried unplugging the MAF, but that did not solve the idle hunting.
For me the Cilinder Misfires are the first priority as it keeps me from driving the car, and i need it for daily usage so yea. Will let you know if the spraying gives me an indication. Thanks for the quick response!
For me the Cilinder Misfires are the first priority as it keeps me from driving the car, and i need it for daily usage so yea. Will let you know if the spraying gives me an indication. Thanks for the quick response!
I think we're saying the same thing. You may have a large vacuum leak that causes your AFR to be out of whack and run crummy. That bad AFR can cause your engine to predetonate or not detonate, generating the P0300. Let us know how it goes!For me the Cilinder Misfires are the first priority as it keeps me from driving the car, and i need it for daily usage so yea.
We've tried your suggestion, and found a small vacuum leak, fixed that but the problem wasn't solved. We have no more leaks anywhere. Would you have any other suggestions?I think we're saying the same thing. You may have a large vacuum leak that causes your AFR to be out of whack and run crummy. That bad AFR can cause your engine to predetonate or not detonate, generating the P0300. Let us know how it goes!
I am not real familiar with the 4 cylinder cars but, you might check out your crank sensor. I have seen them come loose, or get damaged by road debris, the electrical connection may be loose or dirty. Of course it can totally fail, but I would think it that case, it would not run at all. I think something like this is more likely than a vacuum leak problem. ...J.D.
1 - 7 of 7 Posts
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