tmpusfugit

I have had intermittant starts and loss of power on 2 '84's in the last 2 months. In both cases it was the ground strap and they both looked great on the outside and ends, but as Landseer suggests, stripping off the cover I found a lot of gray copper.....it would work, then it wouldn't, then would aqain....no start problems with either since.....other problems, but the start and run is fine.... and I had done the grounds and fuse panel and connectors on both before the ground cables were replaced...

BRB-83-911SC

Thanks Chris. One of the 3 new relays I bought appears to be DOA.

I hear you and the others loud and clear. I just want to start with the simple stuff first before diving into something that may not be necessary and risk breaking something that works - which I have been known to do. I am treating this car with a light hand when troublshooting since so much of it does appear factory fresh. I do know that time can be as much a problem as excessinve use or neglect.

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Thanks. Ground strap will be next if my problem returns.

tv

Yup new relays can be bad, buy em cheap at the Vdub store
Clean all the ground points on the car, like 15 or so
Carry some relays with you and a home made little jumper wire for the fuel relay socket
Buy a spare coil
check condition of your harness
check for water leaking in the CE area
Take apart and clean the engine area wire harness thing (take photo's of it) it's the thing on the passenger side 1 foot up from the radiator, don't let it get wet

The problem you describe can also be the result of a faulty ignition switch, where the key goes. I only ever had the key there, never a key chain. Be surprised on such a low miler but you never know.

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Well, my issue is not resolved - in fact it has morphed into a no start situation in my garage. First thing I did today was replace the battery ground strap with new - still no start. When cranking, I get no tach bounce - does that point to something specific? CPS? All other dash lights and guages are working when cranking. No smell of fuel. I did't have time to do much else today...

Just to recap - relays are good, CE panel is clean and dry, hot post/connector looks like new, caps/rotors good, coil wire ends are clean, battery connections clean and tight.

What is the typical failure mode for the CPS? Intermittant leading up to full failure, or is it all or nothing?

Thanks.

Jadz928

^^^
I think a CPS is an all or nothing part. What can be intermittent about it is it's connector and the one in which it plugs, break down due to heat and wire fray & short. Sometimes starts fine, until things get warmed up, wires touch then no start.

Landseer

At least its in the garage. Not sitting out on the interstate somewhere. (like my jeep last night)

tilac999

Right. In the garage is the best place but still sucks.

Brian, remember when we picked up my car and the owner said the old CPS was intermittent and we replaced it before we went anywhere? Not to throw parts at the problem, but this one may be suspect.

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Yes, in the garage is good. Bummer about the Jeep.

At least it is now sitting in failure mode so I can troubleshoot. I will be taking a look at the CPS connector today, and checking the new relay I just put in the EZF position last week (since it appears I did get one othrer DOA new relay in the batch I picked up).

So, the fact that I get no tach bounce when cranking points to what? Does that point to CPS, or could something else prevent the tach from getting the signal while cranking/no start?

Landseer

When the Perl car had the frayed connector, the tach still moved some, then would hold at 2000 when not running. Weird. Would start and run. Then die. Or not restart. Jim was so frustrated with it he left it sit in the garage for 6 months. Then one day he dove back into it and he discovered the coil corrosion and the fray.

There is an ocscilliscope test for CPS I think. Check the 'test plan' that Mike Frye always talks about for the 85/6 32V cars. Its in the supplemental section of the CD's. I could try to mail it to you w/ email address. The 16V Euro S 84-86 should be nearly identical in test plan. Am headed downstairs to work through it on an 85 today.

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Thanks. e-mail address sent via PM. I have the CD's, so I'll take a look as well. I did see an oscillation graph for the CPS in a thread found on search. I must say, though, that I have no experience doing diag. on electronics. I will have to get my head around this. Should be fun....

Jadz928

Brian,
Digging in back there by the CPS connectors will offer you a good chance to inspect your fuel hoses and the 2 ground point on the backside of the block (LH & EZ harness gnd).

I'm not sure about the crank signal's relation to the tach.
As Chris said, my tach would "pump up" while cranking. And this was with a no start cond. diag'd as a frayed CPS wire (harness side).
See Per Blog in my sig. GL

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OK, I'm going to replace the CPS with new. I have read many threads with this being the solution to problems similar to mine. I have removed the CPS unit, which was easier than I expected. However, I have been unable to unplug the connector. It looks to be in good shape, and I don't want to mess up the harness side. Any tricks to this before I put some muscle to it? Which side (harness or CPS lead) is attached to the bracket? I assume I would pull on the side not attached to the bracket....

Thanks.

tilac999

Is there a wire clip like a square paper clip holding the connectors together? If so pry it off with a tiny screwdriver. I can't remember having trouble when we did mine but then again, I went for coffee and left you guys to finish up

Good luck amigo.

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I am a happy camper today. I came home from work early to find my new CPS at the door, and 30 minutes later my car was running again. Hopefully I will have some time to drive it a bit more this weekend just to be sure my problems are behind me.

A big THANKS to all who commented and provided moral support, and to Landseer who sent me a diagnostic document that, I have to admit, went right over my head. It did, however, help me decide to try the CPS. I was lucky in that the wires and connector looked like new with no signs of degradation. Also, a big thank you to Roger for getting the part to me quickly. And finally, the search button was certainly my friend - learned a lot by reading about similar experiences.

Happy Thanksgiving all.