Go Back   Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Chevy Tech
GL4x4 Live! GL4x4 Casino







Search
Reply
 
Thread Tools
Old February 3rd, 2013, 09:33 AM   #1
bdd1469
bdd
 
bdd1469's Avatar
 
Join Date: 04-12-10
Location: alto mi
Posts: 2,063
iTrader: (1)
Mentioned: 0 Post(s)
Send a message via Yahoo to bdd1469
Default Vortec 5.7 stumble- miss

Ex gf has a 1999 suburban, she said it started acting up about a month ago and has gotten progressivly worse. It runs fine and then acts like someone switches the ignition off and back on. It bucks and chugs under a load, but not all the time.
It throws no codes .

I replaced the plugs, cap, rotor, and plug wires because I have had several no starts from bad cap on vortec motors.

Fuel pressure is 55-60 psi and doesnt seem to bleed down, but I only left gauge on for about a hour.

I know it probobly needs intake gaskeis. I ran out of brake clean so my next step is getting more and searching for a vacume leak around intake.

Im sure it has dirty injectors and could use the sfi to mpi spider upgrade. I dumped a can of see foam in the brake booster line, shut it off and let it sit for a couple hours. It seems to idle a little smoother, but still cuts out.

I pulled the dist to check out the gear as I have heard horor stories. The dist seems tight, and the gear is fine. I realize the timing needs to be checked, but it runs the same as it did.

I want to do the spider if you guys think it could be my problem, but cant just throw money at it.
Any advice would be appreciated.
The best advice I heard so far was dont work on the ex gfs car.
bdd1469 is offline   Reply With Quote
Old February 3rd, 2013, 10:18 AM   #2
Kodiak450r
Keep on truckin
 
Kodiak450r's Avatar
 
Join Date: 11-14-07
Location: Waterford, MI
Posts: 5,909
iTrader: (19)
Mentioned: 0 Post(s)
Default

just about all the 96-99 vortec engines had this issue. most of the time the injectors stick/are dirty. they can be cleaned for the price of some gaskets, or replaced for around 300 bucks. i am having this same issue with my 99 blazer. i plan on swapping to the better injectors.
Kodiak450r is offline   Reply With Quote
Old February 3rd, 2013, 11:08 AM   #3
in2deep
Hole tester
 
Join Date: 05-06-10
Location: fremont,mi
Posts: 1,270
iTrader: (3)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by bdd1469 View Post
Ex gf has a 1999 suburban, she said it started acting up about a month ago and has gotten progressivly worse. It runs fine and then acts like someone switches the ignition off and back on. It bucks and chugs under a load, but not all the time.
It throws no codes .

I replaced the plugs, cap, rotor, and plug wires because I have had several no starts from bad cap on vortec motors.

Fuel pressure is 55-60 psi and doesnt seem to bleed down, but I only left gauge on for about a hour.

I know it probobly needs intake gaskeis. I ran out of brake clean so my next step is getting more and searching for a vacume leak around intake.

Im sure it has dirty injectors and could use the sfi to mpi spider upgrade. I dumped a can of see foam in the brake booster line, shut it off and let it sit for a couple hours. It seems to idle a little smoother, but still cuts out.

I pulled the dist to check out the gear as I have heard horor stories. The dist seems tight, and the gear is fine. I realize the timing needs to be checked, but it runs the same as it did.

I want to do the spider if you guys think it could be my problem, but cant just throw money at it.
Any advice would be appreciated.
The best advice I heard so far was dont work on the ex gfs car.
ex gf dont sound like your problem, if you do work on it atleast get paid for parts and give her some

look at injectors
in2deep is offline   Reply With Quote
Old February 3rd, 2013, 12:05 PM   #4
frdboy
Wishin' I waz fishin'
 
frdboy's Avatar
 
Join Date: 03-29-06
Location: Grand Haven, MI
Posts: 10,444
iTrader: (24)
Mentioned: 4 Post(s)
Default

I would look at the coil, maybe have someone load it while you spray some water on it.
__________________
Cheap Thrills Off Road

2003 F-250 4X4 7.3 PSD Crew Cab

1971 Bronco
frdboy is offline   Reply With Quote
Old February 4th, 2013, 09:16 AM   #5
bdd1469
bdd
 
bdd1469's Avatar
 
Join Date: 04-12-10
Location: alto mi
Posts: 2,063
iTrader: (1)
Mentioned: 0 Post(s)
Send a message via Yahoo to bdd1469
Default

Quote:
Originally Posted by frdboy View Post
I would look at the coil, maybe have someone load it while you spray some water on it.
Thanks thats a good idea.
bdd1469 is offline   Reply With Quote
Old February 4th, 2013, 09:21 AM   #6
bdd1469
bdd
 
bdd1469's Avatar
 
Join Date: 04-12-10
Location: alto mi
Posts: 2,063
iTrader: (1)
Mentioned: 0 Post(s)
Send a message via Yahoo to bdd1469
Default

Quote:
Originally Posted by Kodiak450r View Post
just about all the 96-99 vortec engines had this issue. most of the time the injectors stick/are dirty. they can be cleaned for the price of some gaskets, or replaced for around 300 bucks. i am having this same issue with my 99 blazer. i plan on swapping to the better injectors.
I plan on replacing the injectors and doing a intake gasket, but was hoping to confirm that is for sure my problem first. I dont want to spend 8 hrs and several hundred to find out it's not the problem. I did the sea foam down the pcv line trick hoping it would change something, pointing to a injector issue. It didnt changa anything.

I have read of people with the same symptoms fixing it with different parts. It appears it can be a bad dist, pcm, injectors, fuel press regulator. If it was mine Id just throw parts at it because I like new parts on my stuff. I cant do that here.
bdd1469 is offline   Reply With Quote
Old February 4th, 2013, 09:28 AM   #7
Toyfish
Senior Member
 
Toyfish's Avatar
 
Join Date: 02-05-10
Location: lapeer, MI
Posts: 1,960
iTrader: (28)
Mentioned: 2 Post(s)
Default

Ive had a few 350s act up and it ended up being a bad distributor
Toyfish is online now   Reply With Quote
Old February 4th, 2013, 10:42 AM   #8
bdd1469
bdd
 
bdd1469's Avatar
 
Join Date: 04-12-10
Location: alto mi
Posts: 2,063
iTrader: (1)
Mentioned: 0 Post(s)
Send a message via Yahoo to bdd1469
Default

Quote:
Originally Posted by Toyfish View Post
Ive had a few 350s act up and it ended up being a bad distributor
Thanks

I pulled this one. It feels tight and the gear looks good. It does have cracks where the screws hold the cap down, so Im replacing it today with another used one I have. I will have a freind set the cam retard after I do it and see what happeneds.
bdd1469 is offline   Reply With Quote
Old February 4th, 2013, 11:16 AM   #9
bdd1469
bdd
 
bdd1469's Avatar
 
Join Date: 04-12-10
Location: alto mi
Posts: 2,063
iTrader: (1)
Mentioned: 0 Post(s)
Send a message via Yahoo to bdd1469
Default

Wish me luck!! Found the wire harness that goes to the crank sensor was rubbing on the harmonic balencer. The power steering felt weird at times and the wires going to the pump rubbed through also. Are these a variable pressure pump or something?

I think I may have found my problem.
bdd1469 is offline   Reply With Quote
Old February 4th, 2013, 11:40 AM   #10
frdboy
Wishin' I waz fishin'
 
frdboy's Avatar
 
Join Date: 03-29-06
Location: Grand Haven, MI
Posts: 10,444
iTrader: (24)
Mentioned: 4 Post(s)
Default

Quote:
Originally Posted by bdd1469 View Post
Wish me luck!! Found the wire harness that goes to the crank sensor was rubbing on the harmonic balencer. The power steering felt weird at times and the wires going to the pump rubbed through also. Are these a variable pressure pump or something?

I think I may have found my problem.
Yeah the PS is variable effort. Sounds like you may have it fixed
__________________
Cheap Thrills Off Road

2003 F-250 4X4 7.3 PSD Crew Cab

1971 Bronco
frdboy is offline   Reply With Quote
Reply
Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Chevy Tech
Thread Tools

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 -5. The time now is 10:54 PM.


Powered by: vBulletin, Copyright 2000 - 2012, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
Copyright 2005 - 2012 Cracker Enterprises - Powered by Linux
vB Ad Management by =RedTyger=
Page generated in 0.14146 seconds with 32 queries