1993 4.3 Vortec start/ run problems - S-10 Forum
S-10 Forum is the resource on GM S-series trucks, Suspension, engine information, Body Modifications, painting tutorials.  Modifications to suit every need, budget and whim

1993 4.3 Vortec start/ run problems

Go Back   S-10 Forum > Engine and Drivetrain Tech > 262ci Forum (4.3)
New User? Register Forgot Password


 
LinkBack Thread Tools
Old 02-15-2006, 11:41 AM   #1
Registered User
 
sparks383iroc's Avatar
 
Age: 48
Join Date: Feb 2006
Posts: 211
Location: Under this ****in' Truck in INDY
User is: OffLine
1993 4.3 Vortec start/ run problems

Hello, new member here.

I have and am continuing to search on this subject, but in kind of a rush, my grandmother is in the hospital and I have to go to my Aunt's funeral tomorrow. To top it off, I think I threw a rod in my camaro while running for parts on this problem. Seems like everything is dying on me right now.
Sorry about the SOB intro there, to the topic:

Truck: 1993 Chevy S10 Blazer 4wd CPI Vortec.

Monday morning driving along at constant 55 mph, truck just dies. Pull over to side of the rode and after about 3 minutes, fires up and drives for about 1/4 mile and then dies. Will not fire after this. Wife picks me and takes me to get Iroc and I go to work. Go back at 2:00 pm, fire truck up and runs for ~1.5 seconds and dies. OK, I think it's the fuel pump. Have the truck towed home, put fuel pressure gauge on and get a constant reading of 58psi (spec is 54-62) so that is dead on with no bleed down.


I hooked up my laptop after this and got no codes. TPS output normal. Pretty much everything was normal on the scan, but no start.


Took the Ignition module and had it tested, passed 10 tests, so hopefully eliminated that. Put on new dist cap and rotor. Fired up and ran for 3 seconds then just cuts out. Pulled the plugs and they were saturated. Thought I must not be getting enough spark.


Well, installed new coil, put plugs back in and fired her up. Ran for 30 seconds and then died. Could a faulty regulator cause the injector to flood the engine? (to much pressure). Will take a look at the s10 site. Hoping not to have to replace the injector assembly as that is costly. Thanks for your help and the S10 site info.

When it cuts out, it just shuts off. No stumbling, hesitation and all power still working (lights, gauges and can here fuel pump running).

Any suggestions. Could it be the injector unit?

Sorry if this is choppy sounding, I'm cutting and pasting from posts and emails from Thirdgen.org. Any and all help is appreciated.

Thanks,

Sparks a flyin'


More background: On 12/24/05 the truck started running really erratic, stalled and tripped a DTC. Got it started and drove home with it still running very erratic. (thought it was the fuel pump then, too). Checked fuel pressure then and had proper fuel pressure. I hooked up my laptop and started scanning (using EASE diagnostic system). DTC was 32 EGR. Ok, I thought, just go get an EGR and replace it. Well before I did, I reset the code with EASE software. Low and behold, everything cleared up and the truck has been running perfectly until Monday's events.

Last edited by sparks383iroc; 02-15-2006 at 11:44 AM.
Old 02-15-2006, 12:05 PM   #2
Primer?
 
Tha s-10's Avatar
 
Age: 26
Join Date: Apr 2005
Posts: 511
Location: FAIRFAX
User is: OffLine
Re: 1993 4.3 Vortec start/ run problems

try seeing if the injectors has power

Last edited by Tha s-10; 02-15-2006 at 12:08 PM.
Old 02-15-2006, 12:27 PM   #3
Registered User
 
sparks383iroc's Avatar
 
Age: 48
Join Date: Feb 2006
Posts: 211
Location: Under this ****in' Truck in INDY
User is: OffLine
Re: 1993 4.3 Vortec start/ run problems

Pretty sure they have power. It ran for 30 seconds after installing new coil and letting the spark plugs air out. Are you thinking that maybe it's grounding out and loosing power to it after it's ran for a bit? It is acting like it's getting to much gas. I just pulled another plug and it had gas on it. My wife also just told me she smells gas in the garage (guess I'm a little desynthesized right now, better open the garage door LOL). It's weird the way it cuts off. Like somebody flipped a switch to the motor only, no clue it was going to die at all. During that 30 second run, it idled good and I was able to rev the engine without any problems.

I don't have a voltimeter, so it's going to be hard to check the power on the injector. My scan tool (EASE diagnostics on a laptop) can read all the sensors, will check a recorded log to see if I missed something.

Thanks,
Keith
Old 02-15-2006, 12:27 PM   #4
Registered User
 
Join Date: Dec 2003
Posts: 407
Location:
User is: Online
Re: 1993 4.3 Vortec start/ run problems

I would check the fuel pump relay, battery connections and if you haven't changed your fuel filter recently it wouldn't hurt.

Also, this could be an ignition switch problem

Last edited by jeffawong; 02-15-2006 at 12:28 PM.
Old 02-15-2006, 12:36 PM   #5
Registered User
 
sparks383iroc's Avatar
 
Age: 48
Join Date: Feb 2006
Posts: 211
Location: Under this ****in' Truck in INDY
User is: OffLine
Re: 1993 4.3 Vortec start/ run problems

Quote: Originally Posted by jeffawong
I would check the fuel pump relay, battery connections and if you haven't changed your fuel filter recently it wouldn't hurt.

Also, this could be an ignition switch problem
Replaced the fuel pump relay in June. When I had to replace it I couldn't get the truck to start at all. Already have a fuel filter and getting ready to put it on . Wonder if the relay is the same as the one in my camaro?? Might put that one on and see. Would a relay work sporadically like that? Or are they a work/don't work type of switch? I guess if it overheated, but could it overheat in 3-4 seconds?


Ignition switch? Short in the column?
Thanks,
Keith

Last edited by sparks383iroc; 02-15-2006 at 12:38 PM.
Old 02-15-2006, 12:44 PM   #6
Registered User
 
Join Date: Dec 2003
Posts: 407
Location:
User is: Online
Re: 1993 4.3 Vortec start/ run problems

It sounds to me like something electrical is the prob - if the relay is new I suppose that is not the prob but it should be easy to check (but you need a voltmeter) just jumper the activation wire for the relay and test for the closed circuit

As for the ignition switch - not so much a short but a loss of connection interrupting power for running (this happened to me on another car and drove me nuts trouble shooting it - again here if you want to test you need to check with either a voltmeter or test light - on the ignition circuit harness when the problem happens)
Old 02-15-2006, 12:54 PM   #7
Registered User
 
sparks383iroc's Avatar
 
Age: 48
Join Date: Feb 2006
Posts: 211
Location: Under this ****in' Truck in INDY
User is: OffLine
Re: 1993 4.3 Vortec start/ run problems

Quote: Originally Posted by jeffawong
It sounds to me like something electrical is the prob - if the relay is new I suppose that is not the prob but it should be easy to check (but you need a voltmeter) just jumper the activation wire for the relay and test for the closed circuit

As for the ignition switch - not so much a short but a loss of connection interrupting power for running (this happened to me on another car and drove me nuts trouble shooting it - again here if you want to test you need to check with either a voltmeter or test light - on the ignition circuit harness when the problem happens)
I'm going to try my Iroc relay, something may have shorted it. I bought this truck last year and prior owners had done some crazy (read stupid) things when installing a stereo and apparently trying to fix some other things. I really haven't had to much trouble with it other than fixing there mistakes.

Ignition harness check - from the ignition module to coil ? or start at the switch itself and work my way to the distributor?
Old 02-15-2006, 12:57 PM   #8
Registered User
 
sparks383iroc's Avatar
 
Age: 48
Join Date: Feb 2006
Posts: 211
Location: Under this ****in' Truck in INDY
User is: OffLine
Re: 1993 4.3 Vortec start/ run problems

On the fuel filter, wouldn't a intermittent clog register on the fuel pressure gauge?
Old 02-15-2006, 01:16 PM   #9
Registered User
 
sparks383iroc's Avatar
 
Age: 48
Join Date: Feb 2006
Posts: 211
Location: Under this ****in' Truck in INDY
User is: OffLine
Re: 1993 4.3 Vortec start/ run problems

IROC fuel relay is different, so can't interchange. Time to get a voltimeter.
Old 02-15-2006, 08:16 PM   #10
Registered User
 
Join Date: Feb 2006
Posts: 32
Location:
User is: OffLine
Re: 1993 4.3 Vortec start/ run problems

have you checked the oil pressure sending unit? this will cause the truck to not stay running.
Old 02-15-2006, 09:59 PM   #11
Registered User
 
Join Date: Dec 2003
Posts: 407
Location:
User is: Online
Re: 1993 4.3 Vortec start/ run problems

joe has a good point - I would check the oil sender too.
Old 02-15-2006, 11:02 PM   #12
Registered User
 
sparks383iroc's Avatar
 
Age: 48
Join Date: Feb 2006
Posts: 211
Location: Under this ****in' Truck in INDY
User is: OffLine
Re: 1993 4.3 Vortec start/ run problems

Had to go visit my grandmother in the hospital and a viewing for my aunt. I will try that in the morning. Thanks Jeff and Joe.

Keith

Quick question: Is the oil pressure sending unit the same as the one that feeds the oil pressure guage, or is there a seperate sending unit for the ECM feed? (Like there are 2 for the coolant -one for the temp guage and one for the ECM).


I get a 40+ PSI on the guage when cranking and when it ran.

Last edited by sparks383iroc; 02-15-2006 at 11:31 PM.
Old 02-16-2006, 02:18 AM   #13
Registered User
 
Join Date: Dec 2003
Posts: 407
Location:
User is: Online
Re: 1993 4.3 Vortec start/ run problems

I believe that the oil sender is a 2 in 1 type. It is positioned near the distributor and tough to get at.
Old 02-16-2006, 02:53 PM   #14
Registered User
 
sparks383iroc's Avatar
 
Age: 48
Join Date: Feb 2006
Posts: 211
Location: Under this ****in' Truck in INDY
User is: OffLine
Re: 1993 4.3 Vortec start/ run problems

Ok, got it fixed. It was the pickup coil. Took a voltimeter to it and was getting crazy numbers. Pulled the distributor and found cracked and bare wires. Replaced it and runs fine. Will post pictures later.

Thanks Keith
Old 02-16-2006, 06:17 PM   #15
Registered User
 
needycase's Avatar
 
Join Date: Dec 2002
Posts: 291
Location: Port Saint Lucie, FL
User is: OffLine
Re: 1993 4.3 Vortec start/ run problems

OMG. THIS IS THE EXACT SAME PROBLEM IM HAVING!!! I replaced ignition control module, Fuel pressure realy and oil, and coil.

So your saying it was the Pick Up Coil.... When I replaced the Ignition Control Module the plug to the pickup broke ( it was soo brittle)

But I cant get it to fire up at ALL. I had the same simptoms at first, it died suddenly wouldnt start right away, then did 3-4 min later and would only run for a min or two. No after I replaced the Ignition control module it wont start at all, I took the module to Autozone and had it tested and its fine.

Is the pickup coil a big pain to fix? I know the whole destributor has to come out, but I am a novice AT BEST. and dont want to make matters worse.

Can you lend ANY insite to this matter, I have dealing with this thing for weeeeeeekkkkssss.... And am about to call a tow truck and take it to the dealer and let them fix it.

I also have no fuel tho, I turned the ignition and then with a screwdriver depressed the check valve on the fuel line behind the intake plenum and got a dribble then nothing after that.

I have looked and looked over this forum of late and you have the EXACT same issues I am having. If you get this post before tomorrow let me know.

Thanks!!!!!!
Sponsored Links
Advertisement
 

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the S-10 Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 02:16 PM.

Powered by vBulletin® Copyright ©2000 - 2011, Jelsoft Enterprises Ltd. SEO by vBSEO 3.2.0
SEO by vBSEO
vBulletin Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.