Jumped the gun still having stumbling issues

[-=Jeff=-]

I drove it the other night.. scanned for twice as long as before the car worked GREAT.. nice day figured i would drive it to work.. (about 8 miles) when 1/2 way and needed to get gas.. stumble, and a backfire pop from the TB, pulled in to the station and filled up... Restarted, ran FINE until I pulled in the parkin glot at work.. Same thing TB Pop, then died.. Restart and I have a misfire. I got it parked.. I am guessing when I go to lunch in 4 hours, it will run fine.. cause it will have cooled off.. I am thinking it is definitely heat related..

Coils will be swapped next.. Tuesday night was cool and it was cool the night I drove it in November too, so maybe this issue has been there but did not show up in cool weather.. Not sure what else to check

I did not have my scan tool hook up this am.. probably should have brought it today

[Paul Workman]

Yeah... My training is in electronics, and I agree that it fits a heat-related breakdown somewhere. The coils are easy enough to replace, so I hope that is all it is. (That, among others, was part of my stumbling problem too. The new AC/Delco coil packs seems to have cured the problem - along with replacing the mouse-chewed wires.)

And, although my Z has been running fine with the new ignition stuff, I still store my scanner in the cubby in back...just never know when it might come in handy! But, FWIW, I did not get any codes during the entire time my ignition problems were going on...which makes sense, knowing what the ECM needs before throwing a code.

Like I said...I hope it is just those coils (and not the spark mod). I may be off work on Friday, if ya need another pair of hands...or someone to hold a beer and kibitz while you work!!! LOL!

P.

P.

[-=Jeff=-]

Paul,

I read you older posts...

what did you replace?
Wires, Plugs and Injectors?

[bradslt5]

sure does sound like the coils are going bad .when i first got my black(first) zr1 i had the same problem car ran great for 10 min.,then it sounded like firecrackers .putting the lettle bolts back inthe coil mountings can be an adventure . i used super glue on ths socket stuck the bolt on for a couple of min. then put it in . hope this helped .

[-=Jeff=-]

drove it to lunch 5min away.. it was fine, it sat for 45-50min. drove back.. died parking it again..

at lunch I smelled raw fuel, but there was also a stall truck and wind was blowing from the stalled truck to me, Guessing he had Fuel issues too.

I will check pressure on the injectors when I get home after work. I will pinch off the return line.. I am thinking it is one of these 3:

Coils
Injectors
ECM

that is in no order

I wonder if the ECm has issues when it switches from open to closed loop. Although I felt the stumble in open loop, I also noticed when I pulled in to fill the tank, if I gave it more go pedal it roared back to life.. HMMM

[bobbyhi]

A bad cam sensor can cause the stumbling also..............

[-=Jeff=-]

Originally Posted by bobbyhi

A bad cam sensor can cause the stumbling also..............

would it cause what I have described?

any good way to test it?

[LGAFF]

I am going to say good call on the cam sensor, wifes BMW had similiar issues and no code. Swapped the sensor, and back in business.




LGAFF
92 ZR1
#234

[-=Jeff=-]

Left work.. car ran bad 90% of the way home..

got home.. check Fuel pressure

Key on, not running, Return line pinched.. holds at ~47
key on, not running return line normal, holds at ~47

Coil packs: ohmed out 2 at 20K, 2 at ~18.5K

how hard is to change the cam sensor? WHERE is it?

I NEED the car running by Bloomington Gold, end of June..

this SUCKS

[-=Jeff=-]

Cam sensor should show a Code 31...

I have no SES.. car will load up, stab the throttle and it clears up sometimes..