So my GF was driving the car to work lastnight and it started to act like it wanted to die and the check engine light would come on and off, she made it to work which is close by, and made it home taking surface streets. I used a paper clip to try and pull a code but couldn't find anything, just got the normal code 12. I started the car and the idle is kinda crappy. Any ideas on what could cause the CE light to come on but not leave anything in the memory?
In a day or two I'll replace the cap and rotor and wires, I just did the plugs a couple of weeks ago and the old plugs I took out looked really good also. The car just passed a smog check with flying colors so I think the motor itself is in very good condition. this is an 85 2.8 camaro with auto tranny.

 

Check the battery connections and bulkhead connector. my Bulkhead connector rotted away from battery acid. Driving home car ran like dung and CE light came on. Parked it, got no codes. Fixed the bulkhead and was good to go

 

batt connections look good, what do you mean by bulkhead connector? at first i thought you meant the connector at the firewall near the master cylinder, but you said batt acid got it so it can't be that.
thanks

 

Its bolted to the side of the radiator support next to the battery.

 

Hey, thanks for the terminology, MD! I always called it the "positive junction block"

 

Could be a "six of one, half dozen of the other" terminology. "Bulkhead connector" came out of my mouth when I went to fix it/curse at it.

 

ok thanks for clearing that up, I checked that block and it looked good, I didnt unplug everything and look at the contacts tho, just checked if it looked like it was starting to get attacked by the acid.
Anyhoo, this might be important info: I drove it around quite a bit yesterday and it was fine, my GF takes it to work lastnight and it does it again, now the thing is she goes to work at about 3am, when its cold and kinda wet outside, I'm in California so by cold I mean like 40s or 50s. I'm thinking the temp and humidity has something to do with it, any ideas on what is most likely to be affected by cold damp air?
Hopefully if she has the money we'll get wires, cap and rotor this weekend.
I'm gonna try again to see if I can pull any codes, if I can I'll report back.

 

I know you said it passed smog and you got no codes but it sounds to me like the plug wires, cap, and rotor may be worn out and causing moisture to get in. (just scrolled down and saw you plan to do that) ---Get that done and let us know if the problem persists.

 

Yeh thats the plan, I checked for codes again and there wasn't anything.

 

Ok I've messed with the car some but never really did the recommended stuff because of back probs, it also got bad enough that I could reproduce the problem pretty easily and the car was almost useless. Finally my back got better and here are the results of each step:

1) changed wires, cap and rotor. after this the car ran much better, it now had the power to easily do a burn out, so thinking its fixed I start to test drive, after about 15 mins the prob comes back, CE light in sync with a miss and once it did it while under hard acceleration and I got some loud ping, I back off quick. Overall tho the car still ran better and even when the problem kicked in it wasn't nearly as bad. This time I was able to pull a code, a code 42. I thought maybe one of the new plug wires came loose or something and checked all connections I could find, along with cleaning some grounds. Not Fixed.

2) Changed fuel filter, hooked up fuel gauge. Pressure reads about 37psi and will briefly jump to 40 as I blip throttle. I pinched off the return line (smaller of the two hoses right?) and pressure jumps up to 70 and then wildly fluctuates between 70 and 80psi, so I'm thinking pump is good. Drove it for awhile and problem is still there, but now I can hardly feel nything when the light flashes, and after awhile the light will be constant, and I was able to pull another code 42. While the light was on continuosly while I drove home it seems the fuel pressure was slightly higher and it also idled a bit faster

So any ideas? I don't want to start replacing all ignition stuff without getting some advice first. Also I noticed when I shut the car off the fuel pressure drops very quickly, I plan to look into this more later, can this be related or is it just another future problem?

Later I will start the car and crimp the return line and then shut off the motor, if the pressure doesn't drop as quick then that would mean its my regulator that is messed up right? And if it still drops fast then its leaky injectors, right?

Thanks

 

Ok I crimped the return line (smaller of the rubber lines near the AC compressor) and when I shut the engine off fuel pressure dropped just as fast. Am I correct in assuming its leaky injectors?
Any help on my other post above this one?

 

yes on the leaky injector. 42 code is ignition module i believe and with the symptomology id belive it. could be a bad pickup coil as well.

 

so for the ignition module and pickup coil, are these easy to exchange or do they require completely taking the distributor apart? any tests I can do to narrow things down?