idle missfire??

gjp

gjp

another post whore
Re: idle missfire??

No have not checked the alt yet. I did re-do the ground on the battery. It went strait to the frame so I sanded it clean again and used a new bolt,washer and nut. It starts after a few seconds. has the normal puff of smoke if it sits more than 12 or so hours. The miss comes after its warm so far. some days its bad some days its ok. The truck feels strong. Have yet to time it but I would guess from my experence with my GTP its in the low 13's. I have to get a datamaster on it. I was worried about the pistions or valves but the compression test today was good. The boost also varies a bit with my controler.??? Vacuum again?? I will order a cable soon from somewhere. Thanks for thinking out loud! It helps
 
QUICK STORM

QUICK STORM

B.A.M.F. BMW Tech
Re: idle missfire??

when i had my first ty, i replaced just about every sensor to rule those out, it helps.
 
EcSy#2671

EcSy#2671

Si vis pacem, para bellum
Re: idle missfire??

I'm fighting the same problem. I have new plugs, wires, rotor, cap, bat, and alt. When I went throw with the last tune up it ran great for about 10 mins great idle and everything then back to the way it was, and those the RPM wires. I wish I could help but i'm in the same boat........
 
gjp

gjp

another post whore
Re: idle missfire??

Its gota be vacuum leak somewhere. It explains a lot of what I am seeing. I have built motors before but all have been old school. With all this computer ans sensor crap who knows what it could be. mine ran great for a while too. It runs good wot. (I guess so, i have never been in another sy)
 
gjp

gjp

another post whore
Re: idle missfire??

Started replacing my vac lines. Do I replace the hard lines too with silicone?? please help.
 
gjp

gjp

another post whore
Re: idle missfire??

Tube test???
Ok I replaced my vac lines. I only used 6 feet of the larger line?? Am I missing one. Also the line that goes to the CC colapsed on me?? I cant open it up. weird. I hope its a bad line. Also sometimes the tac will jump around while cruzing on the freeway and does it bad if I tap the brakes with my left foot while holding the gas steady. it will jump 500rpm that way??

Also verry pissed off. My company van broke down. Stupid ford with only 72k!!!! So I took my truck to work and someone hit it. No dent but scrached the $hit out of my pass. fender. :rant:
 
SY2455

SY2455

70's Veteran
Re: idle missfire??

gjp said:
Tube test???
Also verry pissed off. My company van broke down. Stupid ford with only 72k!!!! So I took my truck to work and someone hit it. No dent but scrached the $hit out of my pass. fender.
rant3.gif
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Look at this.

http://www.sytyarchives.com/howto/viewarticle.php?article_name=find_vacuum_leak.php&dir=engine

Sorry to hear about your truck getting hit. Did they leave a note?
 
gjp

gjp

another post whore
Re: idle missfire??

the cruise control


a note. Even if they did, I dont speak spanish!
 
Don W.

Don W.

Stab it and steer it
Re: idle missfire??

Did ya ever get that thing to idle properly? I wonder if some injector cleaner would help? Anyway here's my diatribe on what seemed to clean up my idle:
icon_biggrin.gif


2cents.gif
This is gonna sound weird but while I had my Sy apart this winter for, among other things, new wires, rotor and cap, I pulled the dist and cleaned it up. By that I mean I removed the module, cleaned everything up and, here's the weird part, cleaned the pickup. I actually cleaned between the rotor and stator (don't know if that's the correct terminology) and got rid of as much of the infamous rust as I could.

I also had the IAC off the TB and carefully cleaned the pintle (sp?).

Results: It starts quicker (little bit quicker cold, much quicker hot) and even after a short (10 mile) road trip the thing idles noticeably smother seldom missing at all. No WOT testing was done however. All FWIW
Also vac lines were replaced a year ago using a kit that used to be avail here not sure if it still is but my point is that, as mentioned, functional check valves must be installed in their correct locations/direction for the vac system to work correctly.
2cents.gif
 
gjp

gjp

another post whore
Re: idle missfire??

when cold it idles great. Its on the stock chip and hold a good idle. I will do a 20 min trip. and when I restart is when I lose the idle. The more restarts when warm the worse it gets. After 3-4 restarts it will die when I put into gear or on startup. I have to gas it to keep the idle up a bit. once I get moving it will idle ok at the stops until I turn off and restart? Also the oil pressure bounces a lot. woried because is not the oil pump attached to the end of the dist?? I have replaced all but the cap/rotor (3k on them)and coil. Might do that this weekend.
 
gjp

gjp

another post whore
Re: idle missfire??

I did the tube test. My little compressor could not fill it up. There is a bad leak on the TB on the front by the spring somewhere. It was getting dark so i stopped. I could blow on the tube and hear the leak. it would come out as fast as I can blow it. I guess this is not good. Do I need a new TB.


Also I took apart my cap and rotor. Cap and rotor looked ok but the pickup coil is rusted. Should it be replaced? Also Auto zone gave me a used rotor??WTF
 
QUICK STORM

QUICK STORM

B.A.M.F. BMW Tech
Re: idle missfire??

i think it just needs a rebuild. theres your bad idle and quite possibly a lean fuel trim condition
 
gjp

gjp

another post whore
Re: idle missfire??

Who can do a local rebuild?? My truck also would vary its wot boost from 13lbs to 16 lbs. Might be that problem too.
 
QUICK STORM

QUICK STORM

B.A.M.F. BMW Tech
Re: idle missfire??

gjp said:
Who can do a local rebuild?? My truck also would vary its wot boost from 13lbs to 16 lbs. Might be that problem too.
Click to expand...

i'm not sure. did you search on how to rebuild a throttle body?

and yes this would be related to boost spikes
 
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