Timing problems 5.7 VORTEC HELP!!!!!
 

I have a 2001 3500 cube truck with a 5.7 vortec.For a long time the check engine light comes on going up big hills.For a couple of weeks its been starting funny sometimes kicking back or binding up like the timing is to advanced.Then the other day it wouldent start at all, almost but not ,binding up real bad.I tried replacing the pickup in the distributer but no good.I knew the timing is not really ajustable but I moved it anyway in desperation, then it stopped binding and finnally started altho it was flooded from trying to start for so long.when it got home it started good and for two days since and no light. Did I fix it or postpone A bigger problem? Anybody have any advice or a similer situation? Does anyone know anything about the timing at all?Ive heard some diffrent stories and I dont know much about this truck at all,I finally started to figure out the 5.7 TBI s that we had and then I bought this,Probly figure it out in time to get rid of it also.My 71 is so much easier to get along with!:waah:

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

The timing is a little sensitive. If the distributor has ever been removed (like for the replacement of intake gaskets-common problem), it may be one tooth off. If I remember correctly the timing has to +/- 2 degrees from 0 and has to be fine tuned with a high dollar scanner. If your distributor is in correctly (sounds like it might not be just due to the symptoms) a dealer might be able to set it for just a hour of labor. The sensor in the dist is a cam position sensor. It works with the crankshaft position sensor and when the computer tries to adjust the timing to accomodate driving conditions, it may be adjusting the timing out of sync with the crankshaft position sensor. For more info try looking in the 88-98 forums. Although yours is a 01, this motor also is in the 96-98 1/2 ton trucks and 96-00 3/4 and 1 tons. Run a search.

5.7 Vortec Timing Problems Please Help!!!
 

I posted on the 99 and up board with this but it was lonely over there just 2 people including me.Besides my 71 stakebody dump I have a 2001 3500 box truck that we use for my buisness, when you look under the hood it might as well have a nuclear reacter in there cause its all strange to me.I know this is the older truck page but I know there is a lot of great mechanics on the board and owners of newer daily drivers,that said here goes.For as long as we have had this truck the check engine light comes on going up big hills.Ive had the codes read and no one could tell me why.For about 4 or 5 weeks now the truck has been starting funny ,kind of binding up while turning over like the timing was to advanced ya know.Ive been told the timing was not adjustable,that it was computer controled.Well last week we took it to Boy Scout camp with a bunch of troop gear and after being parked for a week she wouldent start,kept binding up real bad,the battery wore down and the motor flooded.We got a ride home and after getting my sons S10 we went back with a new electronic pickup for the distributor.
installed it Jumped it didnt help ,still bound up.Well I was about to give up when I decided to move the distributor anyway.Well it stoped binding and after a little cranking even though it was flooded it started up.We drove her home about 25 miles up hills and all No PROBLEM and no check engine light. When I started it yesterday it bound a little bit when it was cold but not after the first start. same today and the light is still off.So did I fix it or just postpone a bigger problem? Does anyone know about the timing on these or have anyone heard or had a similer problem? Money is short so I cant run over to the chevy dealer and drop it off.Also on Friday and Saturday we are supposed to use it to transport stuff to my sons BSA Eagle project about 25 miles from home so I dont want to get stuck again and skrew that up! It was bad enough to break down after camp and I had to hear about it from all the Ford and Dodge guys! Sorry again to post this here but I need advice quick Thank you for your attention.

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

The distributor has been out I had to replace the body of it because the ear that the cap skrews down to split and broke off.Why is it made out of plastic?

Re: 5.7 Vortec Timing Problems Please Help!!!
 

best place you can post this is either a) the Engine forum, or b) the General Discussion forum.

Re: 5.7 Vortec Timing Problems Please Help!!!
 

I just replaced the distrib on one of these. The rotor came loose and jammed and actually broke the internal distr.shaft! Anyway, there is a thread already on here about timing this motor from about 2-3 months ago. We just set the distrib so that the flat part in the back was parallel to the firewall and it ran great.(Lucky?) (This was after finding TDC of course) Anyway search here a bit and it is explained how to do it right.

Re: 5.7 Vortec Timing Problems Please Help!!!
 

I had to take the distributer out after I first bought the truck,the truck had no spark so someone said to try the pickup so I changed it and when I went to put the cap back on the ear on the side of the distributer body that the screws go into split open and broke off.I found one in the junkyard but the part on top of the shaft that the roter goes on was bent so I had to change the shaft into it from my distributor.I love my GM's but why do they make the distributer out of plastic?

Re: 5.7 Vortec Timing Problems Please Help!!!
 

This is the best I can help you, but hopefully it's enough. I was browsing around for Vortec info and came across it. I believe it's from the GM Tech manual.

Re: 5.7 Vortec Timing Problems Please Help!!!
 

It is best to find someone with a scanner to set the timing "right" for you. No longer do you use a timing light to time them. You can get it somewhat close by trial and error but it will most likely set the check engine light. If you knew before hand you could have marked the dist housing before moving it to assure getting it back on spot. Got a bud with a scanner or a trusted mechanic? Start with getting that right then work from there.

Re: 5.7 Vortec Timing Problems Please Help!!!
 

:agree: the base timing still has to be set, but it takes a scanner to do it. The computer does control the timing but it works from the base.

Re: 5.7 Vortec Timing Problems Please Help!!!
 

The truck has been running good. my corner mechanic/friend says if the light is staying off it must be awfully close[timing] when I first got it started a light marked security was lit on the dash never even knew it was there and it hasent been on since. Any clue what thats all about? Found a few posts with good info in a forum search on 88-89 page about timing. thank for all the info, this cyber place is the greatest.wish I could stay off the computer long enogh to work on my old truck LOL.

Re: 5.7 Vortec Timing Problems Please Help!!!
 

Just FYI, the timing could be off a couple degrees and affect your fuel mileage while the light is still off. Not saying it is, just a possibility. Tha security light shouldn't have anything to do with your timing. If it's staying off now it was probably a fluke.

Re: 5.7 Vortec Timing Problems Please Help!!!
 

Sorry nothing to say about the vortec timing, but just had to say it is GREAT to hear your son is working on his Eagle Rank!!

I have 2 sons (16 & 19), both Eagle Scouts and was a Scoutmaster for a couple years. Been Scouting for 13+ years but am currently stepping back and getting less involved (been comm. Chair the last 2 yrs.) I missed Summer camp this year for the first time in the last 7 or 8 yrs. I would not trade the time I have spent with my boys for anything in the world!!

Anyway, I parked my '69 in the basement garage in 2001 and let it set while I worked on Scouting. Best decision I ever made! Now I'm starting working on a '99 Suburban that I'm pulling the running gear out of to put in the 69. 5.7 FI Vortec & 4 speed auto, Pwr/heated Leather Buckets, CD, compass in mirror,....who knows how far I will go with it!!

Good Luck on his Eagle!! His Court of Honor will make you the PROUDEST FATHER in the world!!! Try not to cry.

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

Merged, Please don't do this. If you need an original thread moved, please ask. PM, one of the moderators.

From the rules....

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

Sorry about the double post I guess I should reread all the rules,Don't want to make anybody mad here I love coming on here and seeing what everone has to say here,I thought I knew a bit about old chevys but I learn something new evertime I come on here.Thanks to everone that posted on this I know I still have to get it checked to make sure its right on but at least with the ansers and moral support I know she will make it there and back without having to sweat it.I know I have a ton more to learn about this newer truck , hopefuly I won't have to learn to much if you know what I mean. And a big thanks for Woody on the encouragement for my son,we are very proud already.He just spent his seventh and final year at camp as a scout,Ive gone down for some time every year but this was the third year I went for the whole week and the second as an assistant scout master. Tomorrow is the first day of his Eagle project we hope we can get it done in two.Its funny that you chimed in about scouts the first scoutmaster that started the whole troop in our town and ran it for over 40 years was named Woody and our scout building is named in his honer. Well thanks all ,again ,I"ll post the results in a day or so ,for the truck and the kid.

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

Oh just wondering what is that security light?

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

If only fails in high hills you can check the knock sensor.. Check your distributor maybe a module is damaged

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

Truck is running better now than it has since we've owned it,the check engine light did come on briefly on a big hill on the highway today for the first time since the breakdown,so as soon as I get a little cash up I'm gonna get someone to set that timing right and scan the whole thing for problems.Also the son finished up the Eagle project ,it took a whole day longer than expected but its all good. We had 6 scouts 15 - 17 1/2 plus me and my son the first two days and two scouts and us the third day, 8 hour days each. The people at the childrens shelter were very happy with the work.

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

there is tsb talking about bad crank sensor causing bucking when trying to start says to replace sensor i have worked on sevral of these trucks and i know if that dist is not in the right spot it will turn the light on and still run okay there is a mark on the balancer / timing cover and a number 8 mark on the dist/ and rotor , line those two up and lock down your clamp, as far as i know i never had to adjust base timing we have a mac scanner and there is not a option to set timing i never had a running problem after i have done sevral of these dist, i ran into missfiring before on decel before and found the dist gear had about 4-5 teeth shaved very thin replaced with napa and ran great here are two tsb talking about your problem,and disc of dist install

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

Engine - SES Lamp ON/Misfire DTC' Set Towing Uphill

Subject: SES Light and P0300 When Towing, Cruising Uphill or on hard Acceleration - kw 4.3, 5.0, 5.7 accelerate cruise cylinderhead DTC L30, L31, L35, LF6, LU3, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307 P0308 # PIP3081 - (07/23/2004)

Models:

The following diagnosis might be helpful if the vehicle exhibits the symptom described in the PI.

Condition/Concern:

The vehicle may exhibit a SES Light due to a P0300 and misfire. If the misfire is related to the information below, it will typically happen while cruising uphill, pulling a trailer or on hard acceleration and then stop misfiring shortly after returning to an idle. Typically, cylinders 3, 4, 5 or 6 will be the ones to experience this.

Recommendation/Instructions:

If the P0300 SI diagnostics did not isolate a concern, the following may help:

Remove the valve cover, valve springs and valve seals on the effected cylinder or cylinders. A small wire tie or rubber bands can be placed in the valve stem keeper groove to prevent the valve from falling into the cylinder. Rotate the valve while moving it up and down in the guide to see if it binds. If a binding valve is found, remove both cylinder heads and use either of the following methods to increase the stem to guide clearance:

^ Send the head out to a machine shop and advise them to increase the valve stem to guide clearance to 0.002 inch per guide.

^ Hone the guide with a 9 mm hone, such as Snap On BCG249, until a clearance of 0.002 inch is obtained. This will usually take about 4 strokes of the hone.


Reassemble the cylinder heads using new valve seals.

Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance.





Models Affected





Disclaimer

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

Engine - No/Hard/Slow Start/Backfire/Kickback

File In Section: 06 - Engine/Propulsion System

Bulletin No.: 00-06-04-014

Date: April, 2000

TECHNICAL

Subject:
No, Hard, or Slow Start, Backfire or "Kickback" During
Crank/Start, "Grinding" or Unusual Noises During Crank, DTC P0338
(Replace Crankshaft Position Sensor)

Models:
1999-2000 Cadillac Escalade
1995-2000 Chevrolet and GMC SIT Models
1996-2000 Chevrolet and GMC C/K, M/L, G, P Models
1996-2000 Oldsmobile Bravada
with 4.3 L, 5.0 L, 5.7 L or 7.4 L Engine
(VINs W, X, M, R, J RPOs L35, LF6, L30, L31, L29)

Condition:
Some customers may comment on one or more of the following conditions:

^ Backfire during crank/start
^ "Kickback" during crank/start
^ "No" start
^ "Slow" or "hard" start/crank
^ "Grinding" or unusual noises during crank/start
^ Cracked or broken engine block at the starter boss
^ Broken starter drive housing
^ Broken starter ring gear on flywheel
^ Any combination of the above

Cause:
A condition may exist that allows the crankshaft position sensor to command up to 50 extra degrees of spark advance during engine cranking only. This in turn exposes the engine to higher than normal cylinder pressures which may result in an inoperative condition to the starter drive housing, the engine flywheel starter ring gear, or the engine block at the outside edge of the starter boss.

Correction:
Inspect for a stored powertrain DTC code P0338. This DTC will NOT illuminate the "Service Engine Soon" light. If this code is stored, the Crankshaft Position Sensor, P/N 10456607, MUST be replaced and the remaining components inspected for damage (engine block at the starter boss, the starter drive housing, and the engine flywheel starter ring gear).

Notice : When DTC code P0338 is set, failure to replace the Crankshaft Position Sensor could result in repeated inoperative conditions of the starter or flywheel.

Important : Some flywheel wear is normal; broken or missing teeth and/or cracks, are not normal.

Parts Information

Parts are currently available from GMSPO.

Warranty Information:





For vehicles repaired under warranty, use the table.

Copyright © 2008 ALLDATA LLC

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

Got a 98 gmc cabover flatbed, trying to find a spout conncetor for the distri utor to se time.. Any help would be great

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

What is the body of the truck? and what engine? And what fuel system?

There is no spout connector(that's a ford thing). On a 96+ CSFI, there isn't a timing connector, and the base timing adjustment must be performed while using a scan tool.

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

Its a flatbed with a 350.. Spout thing good to know, scanner good to know as well.. How u say that goes, ive got a versus scan tool but havnt got much play time as its a week old lol.. Its oir backup truck, just put new engine in it and it runs like horrible misfire, but no codes,
Unsure how to set base time before using tje light

Re: Timing problems 5.7 VORTEC HELP!!!!!
 

Body is a w4500