C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

HELP! I need help fast!

Thread Tools
 
Search this Thread
 
Old Aug 15, 2001 | 08:21 PM
  #1  
Mike69@ECS's Avatar
0Mike69@ECS
Thread Starter
Former Vendor
 
Joined: Apr 1999
Posts: 7,607
Likes: 1
From: ECS Sales & Service Advisor
Cruise-In III Veteran
Cruise-In V Veteran
Default HELP! I need help fast!

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
Reply
Old Aug 15, 2001 | 08:29 PM
  #2  
kostutsman's Avatar
kostutsman
Instructor
 
Joined: Jun 2000
Posts: 226
Likes: 0
From: Southlake Texas
Default Re: HELP! I need help fast! (Mike69)

what year car?
Reply
Old Aug 15, 2001 | 08:32 PM
  #3  
Mike69@ECS's Avatar
0Mike69@ECS
Thread Starter
Former Vendor
 
Joined: Apr 1999
Posts: 7,607
Likes: 1
From: ECS Sales & Service Advisor
Cruise-In III Veteran
Cruise-In V Veteran
Default Re: HELP! I need help fast! (kostutsman)

It's a 69 Coupe, ZZ4 MSD Ignition, MSD Pro Billet Dist...
Reply
Old Aug 15, 2001 | 08:42 PM
  #4  
kostutsman's Avatar
kostutsman
Instructor
 
Joined: Jun 2000
Posts: 226
Likes: 0
From: Southlake Texas
Default Re: HELP! I need help fast! (Mike69)

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
Reply
Old Aug 15, 2001 | 09:01 PM
  #5  
Mike69@ECS's Avatar
0Mike69@ECS
Thread Starter
Former Vendor
 
Joined: Apr 1999
Posts: 7,607
Likes: 1
From: ECS Sales & Service Advisor
Cruise-In III Veteran
Cruise-In V Veteran
Default Re: HELP! I need help fast! (kostutsman)

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]
Reply
Old Aug 15, 2001 | 09:03 PM
  #6  
flood's Avatar
flood
Race Director
20 Year Member
 
Joined: Dec 2000
Posts: 10,896
Likes: 2
From: CO
Default Re: HELP! I need help fast! (Mike69)

It sounds like one of those things that might clear itself up if you let it dry out for a while. :confused:
Reply
Old Aug 15, 2001 | 09:09 PM
  #7  
Rolling Thunder's Avatar
Rolling Thunder
Safety Car
Supporting Lifetime
10 Year Member
 
Joined: Nov 1999
Posts: 4,466
Likes: 0
From: Paducah KY
Cruise-In I Veteran
Cruise-In II Veteran
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '03
Default Re: HELP! I need help fast! (Mike69)

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.
Reply
Old Aug 15, 2001 | 09:11 PM
  #8  
45ACP's Avatar
45ACP
Melting Slicks
10 Year Member
 
Joined: Apr 2000
Posts: 3,341
Likes: 6
Default Re: HELP! I need help fast! (flood)

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.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-1

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
story-2

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-3

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-4

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-5

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-6

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-7

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-8

2027 Corvette vs The World: Every C8 vs Its Closest Competitor

 Joe Kucinski
story-9

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
Old Aug 15, 2001 | 09:13 PM
  #9  
chevyman's Avatar
chevyman
Racer
 
Joined: Dec 1999
Posts: 351
Likes: 0
From: Connecticut
Default Re: HELP! I need help fast! (Mike69)

Have you tried heating the Ignition with a hair dryer. Its probably has moisture bulid up.
Reply
Old Aug 15, 2001 | 09:14 PM
  #10  
Mike69@ECS's Avatar
0Mike69@ECS
Thread Starter
Former Vendor
 
Joined: Apr 1999
Posts: 7,607
Likes: 1
From: ECS Sales & Service Advisor
Cruise-In III Veteran
Cruise-In V Veteran
Default Re: HELP! I need help fast! (Rolling Thunder)

You can sa
The MSD pro Billet distributor is not very good at sealing.
You 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!
Reply
Old Aug 15, 2001 | 09:16 PM
  #11  
Flareside's Avatar
Flareside
Safety Car
25 Year Member
 
Joined: Dec 1999
Posts: 4,148
Likes: 5
From: Roxbury NJ
Default Re: HELP! I need help fast! (Mike69)

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
Reply
Old Aug 15, 2001 | 09:16 PM
  #12  
Mike69@ECS's Avatar
0Mike69@ECS
Thread Starter
Former Vendor
 
Joined: Apr 1999
Posts: 7,607
Likes: 1
From: ECS Sales & Service Advisor
Cruise-In III Veteran
Cruise-In V Veteran
Default Re: HELP! I need help fast! (chevyman)

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.
Reply
Old Aug 15, 2001 | 09:16 PM
  #13  
Gordonm's Avatar
Gordonm
Race Director
25 Year Member
Liked
Loved
Community Favorite
 
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Default Re: HELP! I need help fast! (45ACP)

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:
Reply
Old Aug 15, 2001 | 09:50 PM
  #14  
a smith's Avatar
a smith
Pro
10 Year Member
 
Joined: Apr 2001
Posts: 605
Likes: 0
From: las vegas
Default Re: HELP! I need help fast! (Mike69)

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.
Reply
Old Aug 15, 2001 | 10:32 PM
  #15  
PRNDL's Avatar
PRNDL
Team Owner
20 Year Member
 
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
Default Re: HELP! I need help fast! (a smith)

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
Reply
Old Aug 15, 2001 | 10:33 PM
  #16  
Mike69@ECS's Avatar
0Mike69@ECS
Thread Starter
Former Vendor
 
Joined: Apr 1999
Posts: 7,607
Likes: 1
From: ECS Sales & Service Advisor
Cruise-In III Veteran
Cruise-In V Veteran
Default Re: HELP! I need help fast!

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]
Reply
Old Aug 15, 2001 | 10:37 PM
  #17  
kostutsman's Avatar
kostutsman
Instructor
 
Joined: Jun 2000
Posts: 226
Likes: 0
From: Southlake Texas
Default Re: HELP! I need help fast! (Mike69)

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
Reply
Old Aug 15, 2001 | 11:50 PM
  #18  
Mike69@ECS's Avatar
0Mike69@ECS
Thread Starter
Former Vendor
 
Joined: Apr 1999
Posts: 7,607
Likes: 1
From: ECS Sales & Service Advisor
Cruise-In III Veteran
Cruise-In V Veteran
Default Re: HELP! I need help fast! (kostutsman)

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
Reply
Old Aug 15, 2001 | 11:59 PM
  #19  
Gordonm's Avatar
Gordonm
Race Director
25 Year Member
Liked
Loved
Community Favorite
 
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Default Re: HELP! I need help fast! (Mike69)

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

Get notified of new replies

To HELP! I need help fast!





All times are GMT -4. The time now is 06:56 PM.

story-0
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-1
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-2
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-3
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-4
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-5
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-6
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-7
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-8
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-9
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE