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Post your sputter, mis-fire, buck, stutter, etc...

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pickens

20+ Year Contributor
544
5
Jan 17, 2003
Southern California, California
Okay, I've have read and seen that a whole lot of DSMs have a mis fire problem that is highly erratic. I've have seen about 100 different threads on this issue talking about a misfire problem. Sometimes these random misfires are extremely difficult to diagnose, so let's gather some collective information into one thread. If you have had a mis fire, studder, spudder, or something of that sort then post the detailed syptoms you seen and the solution that fixed the problem.
 
My misfire only occured under 3/4-to full throttle, over 13psi, and only between 3k-5k RPM. the car would buck hard if I tried to accelerate starting around 3K rpm until I got past 5k rpm and then it would pull fine. Overall power felt sluggish as well. I changed spark plugs, spark plug wires, ICM, and then finally got a new coil that fixed the problem.
 
mine bucks at low rpm's when i give it no gas or bearly any but i ehard its my isc motor
 
I just replaced my ISC motor/BISS with a brand-spankin' new one from Mitsu. That solved my idle surge problem. I also replaced my alternator with a brand new one (old regulator was dead from p/s fluid leaking into it) I also got the car scoped and found out #4 cylinder was having spark problems because of a bad spark plug wire. I had the wires replaced with Bosch premiums (big mistake). Now my car sputters/bucks hard between 2800-3200 rpms during acceleration. The car is running stock boost, no real power mods. I'm thinking its the wires.
 
Originally posted by xxdprussxx
mine bucks at low rpm's when i give it no gas or bearly any but i ehard its my isc motor

This sounds more like a throttle position sensor problem to me. I don't think that the ISC would cause this.
 
I have a 91 eagle and it is having the same problems...
at idle to about 2000 rpms it is surging and miss firing.... I'm thinking it's the plugs or wires... but it could be the ISC.... I have to put it in neutral and rev it up to over 2000 at a light just to keep it running... what do you think it is??? anyone????
 
Originally posted by SpreadEagle
I have a 91 eagle and it is having the same problems...
at idle to about 2000 rpms it is surging and miss firing.... I'm thinking it's the plugs or wires... but it could be the ISC.... I have to put it in neutral and rev it up to over 2000 at a light just to keep it running... what do you think it is??? anyone????

I doubt whether it's the ISC. The ISC only causes a problem when the throttle is closed, as at idle. It is more likely the plug wires. You might look under the hood, in the dark and while the engine is running, to see if you see arcing from any of the wires.
 
When I first got car from auction two weeks ago it barely ran .it would hesitate buck and bog when you stepped on the gas and would make a weird machine gun noise when floored.First put in redline injector cleaner and 91 octane highest you can buy around here not counting gasohol.
Then changed out airfilter to fram for temporary and then put in new fuel filter,pcv and did engine with mopar combustion chamber cleaner.
Then engine flush and amsoil syth.Then o2 sensor and installed apexi catback and downpipe to see if clogged cat was problem.
After all this the car started ok but after heatinng up it started to bog bad wot like before and then as it got hotter it seemed to bog and misfire ,etc thru the range.
Finally today I changed out the coilpacks.Car runs great now.
I bought a new fuel pump incase that was also a problem and need it for planned upgrades.Its not in yet though

So I would change out plugs,wires and coilpacks especially if your car is high miles like mine 130,000. My car now feels like new.I think the factory coil packs get cooked where they are..not much air around them maybe.Just get weak and then won't fire even small gaps.
 
As soon as I get my Accel 7920's wires and NGK BPR6ES plugs installed, I'll let you guys know what difference it makes.
 
Originally posted by PhoenixRPR
I just replaced my ISC motor/BISS with a brand-spankin' new one from Mitsu. That solved my idle surge problem. I also replaced my alternator with a brand new one (old regulator was dead from p/s fluid leaking into it) I also got the car scoped and found out #4 cylinder was having spark problems because of a bad spark plug wire. I had the wires replaced with Bosch premiums (big mistake). Now my car sputters/bucks hard between 2800-3200 rpms during acceleration. The car is running stock boost, no real power mods. I'm thinking its the wires.

I've never had a problem with the Bosch Premium wires. Maybe you just got a bad set or a weak ignition coil.
 
Well I thought my problems were gone but car still seems to have some problems with a bit of bogging ,top end is much better now .So mabye thinking old tps is screwing up but like a lot of parts for our cars they are huge bucks.Mitsu/chrysler sure likes to bend us over the counter..
Parts for my gm cars seem almost free by comparison.But fortunately
non oem parts are cheaper just can't afford the oem ones for some of this stuff.:(

Now to complicate things a bit did just install a maft and gm maf and
some of my problems above might now be simple tuning.

Just wish had a logger to see whats up.But holding off to buy new dsm scanmaster unit on next month or two.
 
I've heard from other people that the Bosch wires/plugs were total crap for our cars? Anyone here agree with this? Also, Mitsubishi told me that the problem we're having with the hesitation sounds like either an ignition coil or possibly the TPS. Lets get some good price lists/sources going for these two parts just in case.
 
bosch arentt hat bad they were good on my 90 talon but when u take them off of spark plug from holes they seem to break
 
Originally posted by swing lo
For a japanese car, use japanese plug's! ngk,denso,etc.

Um, I guess I will do that if I own a Japanese car, but for now, I'll stick to my american Eclipse. :rolleyes:
 
Ok, I'll let this argument drift to the wayside b/c it isn't making progress on a running price list I was hoping for. If you think the car is an import from Japan, that's your prerogative. So far, we've come up with http://www.dsmparts.com selling an ignition coil pack for $179.00 US. We've also found http://www.diamondstarmotorsport.com/elecparts.shtml selling an OEM coil pack for $169.00. Please list any cheaper places as well as good locations for a Throttle Position Sensor.
 
Originally posted by PhoenixRPR
Ok, I'll let this argument drift to the wayside b/c it isn't making progress on a running price list I was hoping for. If you think the car is an import from Japan, that's your prerogative. So far, we've come up with http://www.dsmparts.com selling an ignition coil pack for $179.00 US. We've also found http://www.diamondstarmotorsport.com/elecparts.shtml selling an OEM coil pack for $169.00. Please list any cheaper places as well as good locations for a Throttle Position Sensor.


Damit, nobody said the car was imported man. What do the majority
of the japanese put in there car? If your gonna put afc's,vpc's, and a bunch of j-spec shit on your car, why not do the same with the ignition system?
 
Just turn up the throttle. I got mine idle at about 10,000 not like the standard 7,500. and becreful about any octane booster for your fuel. If you fuel; lines and engine is not use to the higher octane, it will run like crap. try adding small amounts of octane, I run 89% with lucas fuel injector cleaner and my baby purr's. nice...
 
Originally posted by Dragon Talon
Just turn up the throttle. I got mine idle at about 10,000 not like the standard 7,500. and becreful about any octane booster for your fuel. If you fuel; lines and engine is not use to the higher octane, it will run like crap. try adding small amounts of octane, I run 89% with lucas fuel injector cleaner and my baby purr's. nice...

WTF?
 
Originally posted by Dragon Talon
Just turn up the throttle. I got mine idle at about 10,000 not like the standard 7,500. and becreful about any octane booster for your fuel. If you fuel; lines and engine is not use to the higher octane, it will run like crap. try adding small amounts of octane, I run 89% with lucas fuel injector cleaner and my baby purr's. nice...

quoting roast beef.."WTF"..
 
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