0Mike69@ECS

I'm over at another forum members house (RexRuby) cleaning up the engine compartment before Carlisle and now the car idles erratically and backfires at idle.

We wrapped the carb in plastic before we started and went at it with simple green and the garden hose. After we rinsed it, I started the car to let it warm up a little bit and dry off. The car idled fine at this point. We dried up the rest of the visable water and did a little engine touch up - nothing major.

We replaced all hoses and (we never removed any spark plug wires) and did a little more polishing. NOW THE CAR BACKFIRES AND IDLES ERRATICALLY :cry

ARRRRRGH!!!!!!!!!!! :mad

Naturally we pulled the cap - where we found some moisture, but we dried off with John air compressser... Same thing!

What the hell could I have done here we have doubble checked all wires, hoses ect... what else, when combined with water could cause this problem up there?

I need help! I gotta get home!

Thanks!

Mike

kostutsman

what year car?

0Mike69@ECS

It's a 69 Coupe, ZZ4 MSD Ignition, MSD Pro Billet Dist...

kostutsman

This does not sound good - I am concerned that something in the MSD got wet and there is an electrical problem -

You might get this for a minute or so if there was water in the intake you could try running the engine at a higher idle to try to get things warmed up with the attempt to dry out what ever is wet

- once you are past the fuel system the only time something backfires generally is ignition problems - sounds like you are mostly electronic - if the inside of the cap is DRY and the plug wires at the plugs are DRY so that things are not using the water to get to ground the only thing left is the MDS box - did water get in it?

kos

0Mike69@ECS

I have to think it's electrical as well - just because of the water...but...

The MSD box is mounted inside the car, and no it didnt get wet.

One thing there are what look like some black tracing inside the cap... could the water inside the cap cause an arc and burn thorugh the cap - even after it's dry??? Could this cause my problem????

Other than that I see absolutly nothing.... I'm stumped!


[Modified by Mike69, 7:02 PM 8/15/2001]

flood

It sounds like one of those things that might clear itself up if you let it dry out for a while. :confused:

Rolling Thunder

The MSD pro Billet distributor is not very good at sealing. The first thing I would do is take a hair dryer to both the cap and the rotor assembly. Remember, your air compressor generates moisture also.

The next thing I'd look for is a wire to the coil that may have been disturbed during the cleaning process. It's probably something very simple, since it came on quick.

45ACP

My .02-

Let it run + get thoroughly warmed up. The heat will bake out any water causing the mis-firing.

I have no experience with this sort of thing with the Vette, but have been know to partially drown a Jeep or two.

chevyman

Have you tried heating the Ignition with a hair dryer. Its probably has moisture bulid up.

0Mike69@ECS

You can saYou can say that agian there was a substantial amount of water up under there.

I checked out all the little wires and connecters I could and I can't find anything disconnecxted or wet!

I'm going to run up to the local Pep Boys and tray and pick up a new cap... I dont know wheather it will help... but I gotta try something... I gotta get home!

Flareside

Mike, could one of your vacuum lines be off? Maybe you removed them, then hooked one up wrong? If you don't have any idle vacuum at the distributor advance, it will definitely screw up your idle.

-Joe

0Mike69@ECS

I havent tried the hair dryer as of yet. Mayeb I'll give that I shot before I go spring for a new cap. I'll try it and see.

Gordonm

Let it run and dry out. Your wires might be wet where you can't see. The cap could still have a little wetness. Let it warm up and run then let it sit with the hood down. this will dry it completly. The engine might like a little dirt!!! :lol:

a smith

Flareside,Even if the vacuum line on the distrib advance is off it should not matter at idle.The vacuum for that is ported and does not pull any advance until you crack the throttle.I think maybe a plug wire is loose and or wet.Everytime I ever got the inside of the distrib wet the car would not start at all.

PRNDL

So Mike, are you saying you did not mask off the distributor with aluminum foil and plastic bag?? :eek: I always do that when I do the engine cleaning thing, even tho the factory shielding is there already. Another mistake I almost made once was: I first removed air cleaner and air cleaner base and fully covered up carb. Well you know that short fat hose running from the valve cover to the air cleaner base???? That sucker was pointed straight up, just waiting to funnel water into the engine!!!!!

Any progress? MJ

0Mike69@ECS

UPDATE.......... GOOD NEWS
Mike and I decided that a new cap was the most logical next step as we had dried everything and traced out all wires and vac linea and it all looked good. We barely made it to K&G before they closed. Got back to my house, replaced the cap and she fired up flawlessly! Upon closer inspection of the cap, the contacts were in bad shape but Mike and I agreed we've both seen worse on a running engine. So Mike is on his way home to NJ with a big smile on his face :D :D :D :D

OOPs noticed my computer was still logged on under Mike's name......
Signing out, John Porter (Rex Ruby)


[Modified by Mike69, 8:35 PM 8/15/2001]

kostutsman

You gotta let us know how this turns out -

Surely the distributor is tight and the timing has not gotten moved.

I am kinda with everyone else - try to get the engine hot to get things dried out. I am still worried that thnigs may be cross firing from the wet cap - is it real humid up there - getting ti fry may be a problem - what I have seen is the water is condense on the inside of the cap up to an hour after the wash job is complete - sometimes using wd40 to displace the water then drying it out after has done the trick if the humidiy and temperature is the same. 90 and 90

let us know

0Mike69@ECS

NO the engine Dosent Like Dirt Gordon!!!! (I like a dirty Engine!:jester )

Anyway as John said (under my screen name above) we got it fixed with a new cap. Apparently when I first fired the engine (while the moisture was still in there) The spark must have arced through the cap to 4 different cylinders (those little black traces I described above) - even after the cap was completly dry the current must have continued to follow that path - causing the backfire. 25 bucks later - the new cap fixed it. And man was I happy! It was one hell of a backfire. with all the motors I've hosed down in the past (including this one) I've never had a MSD leak so badly!

Thanks a bunch for all the help and Ideas guys!!! I owe you all a beer!!!!

Mike

Gordonm

Good deal. Glad it was an easy fix :D :D :D