changed plugs/wires and still misfiring!?

[blackjdm90]

Hey everyone, i changed my spark plugs and spark plug wires today and i am still misfiring when i hold my car at a certain rpm and at idle i can hear a little bit of a misfire. i am beginning to think that my transistor unit is bad?? i also had to change my alternator and i wouldn't know if that would cause anything like that to happen on my 90 tsi? if any help thanks!!

 

[cyclonekid77]

have you checked your timing lately?

 

[blackjdm90]

no i haven't... the motor just got put in about 10k miles ago. could the timing already be bad or jumped time?

 

[blackjdm90]

but what makes me think it is my Power TR unit is that when my car is started and idling i wiggle the wires around it and touch the transistor pack and my car sounds like it wants to die and the idle changes and the more i mess with it, the more i have to adjust it to get my idle right.

 

[4g63ttuner]

could be a sensor.....ICS mine did the same thing and replaced the ICS and it went away....idk if that was really the problem but it went away

 

[speedfreak58]

check your fuel system. there must be a clog somewhere...injectors, fuel filter, dirty fuel strainer etc

 

[blackjdm90]

could be a sensor.....ICS mine did the same thing and replaced the ICS and it went away....idk if that was really the problem but it went away

i got a price for a new one and its like 175.00 is there any other place that you got yours for cheaper?

 

[cano86]

Do you have a picture or a link of the ICS sensor I might have it or be able to find it for cheap.

 

[blackjdm90]

this is a link to one i found used on thedsmgraveyard.

DSM Graveyard - Your #1 Source for Used DSM Parts!

 

[habitatguy187]

You're on the right track checking the ignition system. It doesn't sound like a fuel issue to me.

Have you done a boost leak test? You might have some vacuum leaks that are causing a misfire. Does it do it all the time or only when the car's warmed up?

 

[cano86]

this is a link to one i found used on thedsmgraveyard.

DSM Graveyard - Your #1 Source for Used DSM Parts!

I dont currently have one of those. Just in case you are not able to order one today I will let you know tomorrow if I find one.

 

[blackjdm90]

You're on the right track checking the ignition system. It doesn't sound like a fuel issue to me.

Have you done a boost leak test? You might have some vacuum leaks that are causing a misfire. Does it do it all the time or only when the car's warmed up?

well somedays it is not bad like 2 days ago. but today it is ridiculously hot outside and when i took my girlfriend to lunch it was doing it bad. pretty much whenever i gave it gas and so i stopped at a gas station and pushed down on the transistor pack and it helped. i was told one time that to test if the Power TR unit is bad put a heat gun or hair dryer to it and see if it changes anything. and with this heat i bet its making it worse... and i am checking my boost leaks soon. thanks

 

[blackjdm90]

I dont currently have one of those. Just in case you are not able to order one today I will let you know tomorrow if I find one.

okay thanks. and its dumb i have a spare 92 tr unit and it wont fit the 90 model. and 90 is the only year that is different it the 1g's

 

[ROOKIE1]

Did you stay with the stock plugs or switch to something else ?

 

[ROOKIE1]

okay thanks. and its dumb i have a spare 92 tr unit and it wont fit the 90 model. and 90 is the only year that is different it the 1g's

, welcome to the bastard year . You will run into that alot .

 

[cano86]

okay thanks. and its dumb i have a spare 92 tr unit and it wont fit the 90 model. and 90 is the only year that is different it the 1g's

I know thats what I noticed.

 

[blackjdm90]

Did you stay with the stock plugs or switch to something else ?

i have been running NGK bpr6es for a while and i just put a new set in. haha and yes this is the bastard year but we got front mount oil coolers stock!

 

[cano86]

If you need the power transitor check this link I saw they have a 1990 power transitor for $39.99 shipped.All the parts listed are in stock and ready to ship. MAKE SURE YOU CLICK THE BUY IT NOW LINK ON THE TOP MENU OF PAGE FOR THE CURRENT PARTS IN STOCK AND READY TO SHIP

Mitsubishi Graveyard

 

[blackjdm90]

If you need the power transitor check this link I saw they have a 1990 power transitor for $39.99 shipped.All the parts listed are in stock and ready to ship. MAKE SURE YOU CLICK THE BUY IT NOW LINK ON THE TOP MENU OF PAGE FOR THE CURRENT PARTS IN STOCK AND READY TO SHIP

Mitsubishi Graveyard

A+ haha i found one for 29.99 on ebay plus shipping so cool i'm saving money. i'll let you guys know if it changes the problem i am having!!

 

[cano86]

Good luck.

 

[blackjdm90]

thanks!

 

[blackjdm90]

RESOLVED!! Ok I ordered a new power tr unit and put it in and the idle was a little better and when I would wiggle the wires on the new power tr unit my car would not die, since it would do this before I thought I fixed the problem. Anyways I was not out of the woods yet, so I started to leave my garage and all of the sudden it bogs down again and is misfiring like no other! So I then start working my way through the ignition system starting with the spark plug wires, I put new ones in and started it and once again I had not fixed the misfiring. I then pulled out my coil pack and began to look at it. Since it was cylinders 2 and 3 that was not getting good spark, I checked those first, I popped off the little black covers to the threaded studs under the pack for 2 and 3 and i saw it! The wires that were going into the studs with a bolt were so loose and wobbling around that there was not a good connection at all. So I pulled out a little 9/32" (or so) wrench and tightened them. Fixed it like a charm and now my car does not misfire at all when I give it full throttle or just cruising!

p.s. Sorry about the long message to explain such a simple fix.

 

[matt98eclipse]

Glad to hear you fixed the problem Patrick! Also thanks for letting everyone know what the issue was i may help out other dsmers

 

[burkgonzo]

Yea thats some good info

 

[blackjdm90]

Glad to hear you fixed the problem Patrick! Also thanks for letting everyone know what the issue was i may help out other dsmers

Haha yeah no problem Matt. I'm stoked that it is finally fixed.