The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1988 - 1998 GMT400 Chevy & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 10-19-2021, 08:11 AM   #1
straight6chevyguy
Registered User
 
straight6chevyguy's Avatar
 
Join Date: Dec 2018
Location: yamhill OR
Posts: 783
Random multiple cylinder misfire when wet/damp outside

Hi guys my truck has been having some engine misfire problems lately.
Truck is a 1998 Chevy 1500 4.3 V6 5 speed manual.

When ever the weather is wet or damp outside the truck jerks really bad at cruising speeds.
It seems to smooth out if I stomp on the gas.
Getting a code for random multiple cylinder misfire.

I have checked the dis cap and it seemed fine.

Any help would be great thanks ahead.
__________________
1965 chevy c20 292 4speed http://67-72chevytrucks.com/vboard/s...d.php?t=777601
1976 chevy c10 250 4speed http://www.67-72chevytrucks.com/vboa...d.php?t=787037
1998 chevy c1500 4.3L 5speed (My current driver)
2002 Chevy s10 4.3L auto 4x4
1971 mercury monterey wagon 400 auto
To many projects!
straight6chevyguy is offline   Reply With Quote
Old 10-19-2021, 01:00 PM   #2
Just call me Sean
Registered User
 
Just call me Sean's Avatar
 
Join Date: Jun 2014
Location: Orlando Florida
Posts: 1,598
Re: Random multiple cylinder misfire when wet/damp outside

With mine it was the distributor cap.
__________________
Quote:
Originally Posted by Early Cuyler
Fights begin, fingerprints are took, days is lost, bail is made, court dates are ignored, cycle is repeated.
Just call me Sean is offline   Reply With Quote
Old 10-20-2021, 04:58 PM   #3
Snarl95
Registered User
 
Snarl95's Avatar
 
Join Date: Jan 2019
Location: edenton nc
Posts: 76
Re: Random multiple cylinder misfire when wet/damp outside

How old are the plug wires?
__________________
1995 k3500 cclb srw 6.5 turbo diesel.

The lessons that hurt are the lessons that teach.
There is always a price to pay.
You are free to make any decision you want. You are not free from the consequences.
Snarl95 is offline   Reply With Quote
Old 10-30-2021, 01:03 PM   #4
straight6chevyguy
Registered User
 
straight6chevyguy's Avatar
 
Join Date: Dec 2018
Location: yamhill OR
Posts: 783
Re: Random multiple cylinder misfire when wet/damp outside

Quote:
Originally Posted by Snarl95 View Post
How old are the plug wires?
Something like 2 years old
__________________
1965 chevy c20 292 4speed http://67-72chevytrucks.com/vboard/s...d.php?t=777601
1976 chevy c10 250 4speed http://www.67-72chevytrucks.com/vboa...d.php?t=787037
1998 chevy c1500 4.3L 5speed (My current driver)
2002 Chevy s10 4.3L auto 4x4
1971 mercury monterey wagon 400 auto
To many projects!
straight6chevyguy is offline   Reply With Quote
Old 10-30-2021, 01:18 PM   #5
straight6chevyguy
Registered User
 
straight6chevyguy's Avatar
 
Join Date: Dec 2018
Location: yamhill OR
Posts: 783
Re: Random multiple cylinder misfire when wet/damp outside

So I swapped out the dis cap with an old one that came off my Dads van.
The truck ran better for a few days and then started doing pretty much the same thing as before.
This being said, when the truck isn't jerking/misfiring it seems to run better with this cap then my other one, so pretty sure there's something wrong with my other cap maybe this one too.

So anyway I went ahead and ordered new plugs,wires,cap and Rotor. should be hear within the coming week.
__________________
1965 chevy c20 292 4speed http://67-72chevytrucks.com/vboard/s...d.php?t=777601
1976 chevy c10 250 4speed http://www.67-72chevytrucks.com/vboa...d.php?t=787037
1998 chevy c1500 4.3L 5speed (My current driver)
2002 Chevy s10 4.3L auto 4x4
1971 mercury monterey wagon 400 auto
To many projects!
straight6chevyguy is offline   Reply With Quote
Old 10-30-2021, 08:13 PM   #6
LT7A
Registered User
 
Join Date: Oct 2015
Location: PNW
Posts: 3,472
Re: Random multiple cylinder misfire when wet/damp outside

Did they do the same thing with the 4.3 that they did with the V8s and try to have conductors crisscross the cap so that spark plug wires all came off the cap on the same side of the engine where the plugs are? If so, those caps are really problematic for the V8s, and there is a thread on here somewhere for that.
LT7A is offline   Reply With Quote
Old 10-31-2021, 12:20 PM   #7
straight6chevyguy
Registered User
 
straight6chevyguy's Avatar
 
Join Date: Dec 2018
Location: yamhill OR
Posts: 783
Re: Random multiple cylinder misfire when wet/damp outside

Quote:
Originally Posted by LT7A View Post
Did they do the same thing with the 4.3 that they did with the V8s and try to have conductors crisscross the cap so that spark plug wires all came off the cap on the same side of the engine where the plugs are? If so, those caps are really problematic for the V8s, and there is a thread on here somewhere for that.
Yes they did the same thing.
Yeah I have read stores on this forum and others about these caps. Mostly quality issues
From caps failing in short periods time to them being bad new out of the box.
__________________
1965 chevy c20 292 4speed http://67-72chevytrucks.com/vboard/s...d.php?t=777601
1976 chevy c10 250 4speed http://www.67-72chevytrucks.com/vboa...d.php?t=787037
1998 chevy c1500 4.3L 5speed (My current driver)
2002 Chevy s10 4.3L auto 4x4
1971 mercury monterey wagon 400 auto
To many projects!
straight6chevyguy is offline   Reply With Quote
Old 11-03-2021, 12:40 AM   #8
straight6chevyguy
Registered User
 
straight6chevyguy's Avatar
 
Join Date: Dec 2018
Location: yamhill OR
Posts: 783
Smile Re: Random multiple cylinder misfire when wet/damp outside

Put on the new cap and rotor today. The truck is running way better.
I'll give it a few days of driving to work and back before I call it a for sure win.
__________________
1965 chevy c20 292 4speed http://67-72chevytrucks.com/vboard/s...d.php?t=777601
1976 chevy c10 250 4speed http://www.67-72chevytrucks.com/vboa...d.php?t=787037
1998 chevy c1500 4.3L 5speed (My current driver)
2002 Chevy s10 4.3L auto 4x4
1971 mercury monterey wagon 400 auto
To many projects!
straight6chevyguy is offline   Reply With Quote
Old 11-03-2021, 11:27 AM   #9
hatzie
Moderator
 
hatzie's Avatar
 
Join Date: Oct 2008
Location: Wentworth, NH
Posts: 4,911
Re: Random multiple cylinder misfire when wet/damp outside

Quote:
Originally Posted by LT7A View Post
Did they do the same thing with the 4.3 that they did with the V8s and try to have conductors crisscross the cap so that spark plug wires all came off the cap on the same side of the engine where the plugs are? If so, those caps are really problematic for the V8s, and there is a thread on here somewhere for that.
That was definitely a solution in search of a problem. They found one...
__________________
1959 M35A2 LDT465-1D SOLD
1967 Dodge W200 B383, NP420/NP201 SOLD
1969 Dodge Polara 500 B383, A833 SOLD
1972 Ford F250 FE390, NP435/NP205 SOLD
1976 Chevy K20, 6.5L, NV4500/NP208 SOLD
1986 M1008 CUCV SOLD
2000 GMC C2500, TD6.5L, NV4500
2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263
2009 Impala SS LS4 V8


RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...Please include at least the year and model in your threads. It'll be easier to answer your questions.
And please let us know if and how your repairs were successful.
hatzie is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


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


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com