They normally are… lol
Yeah, it would actually start normally when it was in this condition or nothing at all. It was rare but sometimes struggled, clicked, and then started, usually while I was having problems.
I wonder if the wires were simply touching internally. Of course me working on this disturbed things and would seem to re-establish connection and it would work for a period of time ranging from hours to close to a year.
I am sure it wasn’t always perfect while it was working which cause the premature failures as you mention.
Yep! I had something similar once before. The sensor grounds were dirty or corroded where they mated to the intake. I was having intermittent poor running issues on cold damp days on start and then it was fine the rest of the day.
It would be hard to start and once it started, it would stumble and misfire, popping out the exhaust. The exhaust would smell like an old stinky two stroke boat motor while doing this as well. It would do this for a few minutes and then be fine the rest of the day unless it sat 8 hours or so and was cold and damp when I returned.
I figured it was something electrical but didn’t know where to start. I never had any check engine lights or pending codes throughout all the months I was dealing with this. Anyway, I was telling someone about how it would do this and then run like a champ once warmed up. He told me to remove all the sensor grounds from the intake and to clean the eyelets as well as the mating surface on the aluminum intake. They didn’t look dirty or corroded but I could see this job would only take a few minutes so decided to proceed. I removed them and cleaned everything up with fine steel wool, then wiped down with a rag soaked in carb cleaner. I then coated the contacts with silicone grease and re-assembled.
Apparently my months or a year or more of fighting this was caused by a simple and easy to overlook problem. It was just good to talk to someone who had experienced the same thing and knew what to do. Again, it is a real pain when you don’t get any OBD codes at all and have no idea where to start. I was checking engine compression and all was well. Again, the connections didn’t even really look dirty or corroded but apparently that was the problem. It wasn’t like my solenoid wire where it was blatantly obvious once I cut into it.
The one that ate my lunch was when I had my shop and had a T-Bird towed in crank no start… I did all the checks etc etc etc and everything pointed to the computer, so I ordered one and installed it and it still didn’t start… So I did ALL the checks and everything pointed to the computer again… The 1st computer took a while to get (back in the late 90’s) and I just didn’t think that 2 computers had the exact same issue… Well being the good little tech that I was I had fender covers all on the front… I removed them and went to hook the battery up from doing a ohms check on the wires going from the computer, and I noticed a small ground wire coming out of the harness broke over the inner fender close to the battery, so I thought I must have broke it while leaning over the fender… When I went to repair it I noticed corrosion and so I repaired it and put it back together and thought I would just try to start it just for haha’s and it started right up. lol… Well needless to say I am an honest guy and only charged for a standard diag and had a spare computer until I finally sold it or something, didn’t have eBay back then… You live and you learn…
It is amazing how something so small can be such a show stopper. I did try to start the car in question when I had the grounds disconnected and it would just crank but not start as was the deal in your case.
I never had a check engine light throughout all the months of dealing with my bad grounds.
That “secondary solenoid” on your firewall is a simple relay.
This is what I am talking about for the firewall solenoid. Amazon.com
300 plus miles So far I have had no problems since the one incident.