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Sputtering... CPS? Pump? ECU? Help!

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Blitzeclips

15+ Year Contributor
1,571
6
Aug 5, 2004
Bear, Delaware
Well as you can probably see with my thread history I have been having a problem with sputtering while I drive my car. It's becoming a daily thing and to the point where I'm about to drive this car off a damn cliff.

Basically, the car will randomly shut off at idle, or while I'm driving. But it doesn't necessarily cut off, I'll be driving and the car will begin to buck very very hard, I think it's because of the fact that I'm driving and already applying throttle when the car begins to die; therefore it won't fully shut off in the middle of a drive but it will just buck very very hard for a few seconds and then drive like normal.... but not quite. The car will sometimes hesiate to accelerate and sounds weak. It doesnt always happen though, sometime I can start the car and take a trip without the problem. But 80% of the time this happens. It's been getting worse. It's almost as if someone is cutting fuel supply or somethng, but I have no leaks or anything.

I am thinking it's either my ECU or CPS. I've heard f**ked up things happen when you CPS goes out but I don't know exactly how to tell if that's the case. I'd like to buy an ECU but if the CPS is the issue then I wasted money the the ECU. Vise versa for the CPS.

My questions to you guys....
1) Would this be a common problem with the ECU? Or CPS?
2) Is there anyway I can check these to see if they need to be replaced?

If these don't fix it I'm moving onto either my fuel pump or possibly my FMU...

Thanks in advance for any help. I am trying to figure this out before I'm left stranded in the middle of center city Philly . OMG
 
More often than not, it's plugs/wires that causes shit like this, however that generally happens regularly, under load. If it's bad plugs/wires, easing off on the throttle (reducing engine load) tends to abate the symptoms.

95s are prone to ECU failure more than any other DSM, so it's a possibility, but CPS/CMP failure is easily diagnosed. Backprobe each sensor at the ECU connector while cranking. You should see the alternating 5VDC there. If you do not, then backprobe the sensors themselves. If you get the 5VDC there, then suspect a short in the lines, some of which run along the EGR tube (if you've still got it).

Then again, as loss of either of these signals to the ECU trips the ASD, you should pick up a CEL in the process. If you've got no CEL, you might give these things a try while waiting for your new ECU to arrive, imo.
 
Failing ECU's aren't know for causeing bucking issues. The very hard bucking is most likely the crank sensor (CAS) causing ignition failure. Very common problem in 95-96 models, this is why they revised the sensor for the 97+ models. If you buy a new sensor it will be the 97+ sensor and comes with a pigtail to attach to the wiring harness. Been there already had this problem. My car would buck and then eventually die, Id let it sit 5 minutes it would fire back up.
 
Failing ECU's aren't know for causeing bucking issues. The very hard bucking is most likely the crank sensor (CAS) causing ignition failure. Very common problem in 95-96 models, this is why they revised the sensor for the 97+ models. If you buy a new sensor it will be the 97+ sensor and comes with a pigtail to attach to the wiring harness. Been there already had this problem. My car would buck and then eventually die, Id let it sit 5 minutes it would fire back up.

So if it comes with a pigtail at the end will I have to rewire the sensor completely or just unclip the side of the sensor with the pigtail and plug the other side into the block?
 
So if it comes with a pigtail at the end will I have to rewire the sensor completely or just unclip the side of the sensor with the pigtail and plug the other side into the block?

The sensor and the clip/harness connection come together. You will replace the old sensor and you will also replace the connector that you plug into the new sensor by cutting the old one off and soldering in the new pigtail to the wiring harness.

I mean, if you just want to see if thats ultimately the problem before upgrading, just go to a junk yard and look for the old 95-96 sensor from a 95 or early 96 eclipse/talon/or neon. The old sensor is Commonly seen in a neon green color. Swap it first and test it out.
 
Sorry to bring up an old thread but I was wondering if you resolved your problem Blitz. Mine is doing the same thing but I haven't checked my spark yet. A coupld of years back I used to have intake backfire and it happened to be my wires. This time it would buck on a steady load or when I let off the throttle
 
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