92 runs rough with no power until WARM???

[JAG63]

Hello i recently purchased a silver 92 in immaculate condition, the only problem is when it is first started COLD it has no power and stumbles and falls like 2 cylinders are dead CEL is ON. once it is warmed up the idle clears up it runs smooth and responsive and the CEL goes out. i have owned many SHOs but i have never had one act like this. any ideas??

i ran the paper clip test and with the KOER i got

111 System Checks ok

i then ran it with the KOEO and got

211 Ignition PIP signal was erratic or missing – Ignition Systems

215 Primary circuit failure – ignition coil 1 – Ignition Systems

216 Primary circuit failure – ignition coil 2 – Ignition Systems

542 Fuel pump open, bad ground or always on – - Power / Fuel Pump Circuits

i would like to mention after doing the KOER test it stalled, i then restarted it and had a hard time, i had to WOT and crank to get it to fire so i wonder if this caused a few of the codes? i was leaning towards a stuck open EGR valve but i would really like your opinions as i am not to familiar with mechanical issues and these cars i had good luck with most of mine in the past.

any and all info is greatly appreciated

thanks

Joe

 

[SHOdded]

Could be a crank sensor or associated wiring/connectors. I assume the tach does move when you crank the engine? If the tach does not move, then check the cam sensor to see if it is leaking/soaked in oil. Then I'd check the DIS for proper grounding, heatsink compound behind the DIS, and tight connections. Finally, the coil pack may indeed be at fault, though this is rare. Is there anything leaking onto the coil pack? Could be coolant spray from the hose to the throttle body or PCV fumes from loose intake manifold hoses.

 

[rubydist]

you need to replace either the dis or the coil pack. my experience is 50/50 with the coil codes being dis v. coil. there is also a slight possibility that the pcm is bad.

you need to make sure that the 211 goes away, or else you will need to replace the crank sensor. that code could be a phantom from the dis or pcm, but if it is real then you will eventually end up stranded on the side of the road.

 

[JAG63]

OK thanks. Now if the dis is indeed at fault would the symptoms get better once the car is warmed up at operating temperature? I had an Sho that wouldn't start once and it was just a loose connection on the dis. I have a super coupe Thunderbird for parts is the dis the same off of that? Thanks

 

[JAG63]

i would also like to mention it looks like someone installed a brand new MAF sensor, probably a bad mechanic throwing parts at it is my guess

 

[rubydist]

the dis is the same on the supercoupe.

it is possible that the dis is not happy cold but is okay warm, although more typically electronic stuff is the other way around. that is another good reason to check for connector issues very carefully, because it is more likely that a connector issue would get better once it is warm.

 

[JAG63]

ok thanks, i have a few DIS laying around, i will check thoroughly for connection and ground issues then i will swap out the DIS, when i picked up the car the battery was dead and i had a to charge it, would low voltage cause a strange acting DIS? i really appreciate everyones time thank you

 

[rubydist]

low voltage can cause the dis, the pcm, and the coils each to have issues.

 

[JAG63]

low voltage can cause the dis, the pcm, and the coils each to have issues.

hmmm, maybe i should just buy a new battery first then?

 

[rubydist]

if you have enough juice in the battery to start the car every morning, you are unlikely to have a low battery voltage issue to cause you problems. if you do, its an alternator issue, not battery.

 

[JAG63]

no the battery seems very strong and while running the alternator seems like it is working fine but i will look into it, thanks ruby

 

[JAG63]

thank you everyone for the help it was indeed the DIS Module, i didnt have any heat sync **** so my new question is will it be ok for a while to run it without any until i can do a 60k service on the car?

 

[SHOdded]

Do not risk the DIS! Always put a thin layer of the heatsink paste on the back. Best stuff I've found is any heatsink paste used for computer processors. You can use dielectric grease as a backup paste, but it does not work nearly as well as heatsink paste.

A heated debate here: http://www.shoforum.com/showthread.php?t=58423 Enjoy

 

[JAG63]

Do not risk the DIS! Always put a thin layer of the heatsink paste on the back. Best stuff I've found is any heatsink paste used for computer processors. You can use dielectric grease as a backup paste, but it does not work nearly as well as heatsink paste.

A heated debate here: http://www.shoforum.com/showthread.php?t=58423 Enjoy

i just read that entire thread, great arguments there, i will buy some heat sink compound :thankyou: