Hi everyone, I have begun to experience a strange problem with my 1993 Celsior. If I dont start it for three or four days it misfires like crazy on startup and continues for a few minutes and then fixes itself and works fine.

This ONLY happens if it doesn't start for three or four days....once it starts after the misfire goes away it is as good as gold and if I remember to sart it every day of two it has no misfire problem on starting whatever and runs great. Any ideas as to what may be causing this? Remember it runs great if i start it regularly....

 

My thoughts:

• Engine ECU
• Check plugs for fouling
• Injector

 

Those would be all reasonable if the car didn't run perfect otherwise. The ONLY problem it has shows up after it hasn't started for three or four days. After the misfire clears itself it starts and runs just fine for days and days.

 

when was the last time the ignition caps and rotors were replaced? slight moisture in there can cause misfires, which would clear once the contacts are used. they could also just be old!

 

Hey Timmy, thanks for taking an interest. I never thought of that. As it happens I have alrady had to change the cap and rotor on the right bank but the left bank still has the original parts. Now let me ask you what you think about the chances of it being an injector problem as opposed to the cap and rotor.

You see when the misfiring is in progress it cannot idle so I have to keep the revs up and I also blip the throttle until it clears - which happens suddenly after two or three minutes (maybe even four) - and then it immediately smooths out and behaves as if nothing ever happened and It will remain problem free as long as I start it regularly.

 

injector could also be an issue, but i always try the easier path first before diving into more complex things. granted injector is not overly complicated but harder to diagnose compared to the ignition components. speaking of, how are your spark plug wires?

also it would be worth a shot to just push connectors/plug wires together to make sure they are all seated well, including the injector electrical connectors!

 

My initial thought is consistent with Timmy re cap/rotor and maybe ignition wires.
To expand on it a bit-
Is the car garaged or parked outdoors?
If kept outdoors, is there any correlation between the misfire and rainy weather or a source of high humidity?

 

Ok Timmy, thanks for your input. You have given me more confidence now together with a better direction and a bunch of things to try. I'll start with the basic maintenance stuff like the plug wires and injector connectors and after that I'll move on to the other cap and rotor.

I'll remember to post my progress so you and others will maybe be able to apply it when and if necessary or at least add to the general store of knowledge that is such a great resource on this forum.

Have a greeat day.............

 

What was the verdict? same issue right now, sounds like a nascar

 

Hi StockLS, Timmy and others

Ok I began at the beginning as suggested by Timmy and removed all the plugs, cleaned them and re-intalled with some dialectric grease on the HT connections. The plugs all looked fine with no discernable difference between cylinders. I examined the plug wires and repaired a small superficial outer tear on one of them. I removed the wires from the distrubutors and coils and cleaned and relinstalled with dialectric. I removed and sprayed CRC 226 into the igniter connectors, the MAF, injector connectors and buttoned everything back up proper.

All that minor maintenance seemed to have fixed the problem at least for now - with these older cars you never know. It will now start right up even after a few days down so fingers crossed. If it happens again I will look into changing the plug wires. What I initially thoiught was a fuel injector problem apparently (again as Timmy suggested) was not.

Thanks StockLs for reminding me to update my progress. Good luck guys and stay copacetic ......