I have a 1997 Elcipse GS-T with the 2.0 turbo engine.

I have an ignition miss. This is an interemittant miss. It doesn't occur when the car is cold. It usually occurs after I have driven the car and turned if off for a short period of time.

The car won't rev above about 1500 RPMs and misses very badly.

Today it happened on the way home. So I put a timing light on each spark plug. Number 2 and number 4 were firing irregularly and when I reved it up they dropped out all together. These cylinders are fired by different coil packs. So I am assuming the coil packs are not the problem. The car does run, so I am assuming the Crank Position Sensor is ok. This leads me to the Cam Angle Sensor. I removed the cover on it and wipe away some oil but it didn't help. Is there anyone to test this part without the part tester that the manual says you need? Also could the power transistor bad? The plugs and plug wires are ok.

What else could be the problem?

Thank you in advance for your help

 

Based on what you stated here are some ideas that I have that might contribute to this problem.
When you say that cylinder 2 and 4 drop out, do you mean they quit firing or have no spark or both?
Assuming you have weak or no spark:
If each cyclinder fires from a different cyclinder pack then I would check the voltage to each plug. If the voltage is low then the engine will run and start to miss at higher rpm due a weak spark and an incomplete burn.
Assuming you have complete spark:
You could have underfueling. If you have bad injectors in those two cylinders then it is possible they may not be delivering enough fuel.

Here is a quick list of things that I know cause missfiring (some you have already been covered).
1. Spark plugs.
2. Spark plug wires.
3. Vacuum leaks.
4. Faulty ignition.
5. Inproper compression.
6. Faulty injectors.

Are there any other symptoms you can add?

 

Pilot,

This sounds classic for an ignition module that's going out; #4 on jc_ride's list.

Good luck, Jeff

 

Thanks for the reply.

First I have made some assumptions in my diagnosis and now I have to go and explore them deeper. When I say cylinders 2 and 4 drop out. I mean they have no spark. This was tested by putting a timing light on each spark plug wire. Therefore, you may be correct. I could have low voltage. If the voltage isn't high enough to jump the gap on the plug my timing light probably would not trigger.

1. I have removed, cleaned, and gapped the spark plugs. The appear to be in good shape.
2. The plug wires are a few years old and they appear to be in good shape. I may rearranged them on the car to see if I can get a different cylinder to mess up, and thus determine if they are bad. I really don't think they are.
3. I haven't even thought about vacuum leaks. I guess I could pull out the propane torch and check for them, but this is an intermittent problem and the car runs fine otherwise.
4. Faulty ignition. This is what I think the problem is and I'm looking for help in determining what part of the ignition is bad.
5. Compression. I haven't tested it, but considering how well the car runs when it's not acting up, I don't think this is the problem.
6. Faulty injectors. I don't think this is the problem. Once, when I removed the plugs while the car was acting up, the two plugs on the cylinders in question were very black and sooty. Otherwise they were cleaner than the other two plugs. So I am assuming that fuel is getting to those two cylinders and not getting lit, and thus washing the plugs. Lastly, when I have the miss is is accompanied by loads of black smoke and a strong gasoline smell in the exhaust. So I'm getting plenty of fuel coming out of the exhaust. This is mostly likely from the two cylinders not firing.

Jeff. Thanks for pointing to the ignition module. This was something I suspected. I'll go test it today.

A mechanic friend suggested checking the timing belt. I doesn't make sense to me, but he says it could have stretch a bit and got the CAS timing a bit out. I don't think this would cause the car not to fire the plugs but he said if the CPS and CAS readings are too far out then the computer will get confused. Does this make any sense to you guys?

 

Pilot,

I've never had my hands on the Mitsubishi 2.0 engine, but would be thoroughly surprised if Mitsubishi moved the crankshaft sensor to a camshaft. The crankshaft sensor tells the computer where the crankshaft is in it's rotation so the computer can decide if it needs to advance or retard the ignition timing for performance, emission or detonation reasons. Your engine has a timing belt tensioner which prevents slack from forming in the belt. The only way slack could from is if the tensioner failed (which does happen if you have the non-spring type tensioner). When that occurs the belt will incrementally jump teeth until the engine will no longer run. You'll have fire, but you won't have enough vacuum in the intake that the engine will run.

The ignition module which I was refering to is probably inside your distributor.

Good luck, Jeff

 

Jeff be prepared to be thoroughly suprised. Acutally you'll probably be totally dumbfounded.

I don't mean to be a dick, but why are you telling someone what to do if you have never seen the engine?

The Mitsbushi engine has a Crank position sensor and a cam angle sensor. Most every car made these days has both of these sensors.

Also, the Mitsubishi doesn't have a distributor. I can't think of any car made in the last ten years that has a distributor. I'm sure there a few still made like that, but they would have to be some old junk the U.S. car manufacturers are still selling.

 

Pilot,

I am surprised; and last week I replaced the ignition modules in a 96 Galant (in the distributor) and a 94 Seville (no distributor).

For my education, what is the function of the cam sensor?

Thanks, Jeff