I am going to burn my truck!

Anonymous-0 · Sep 3, 2012

I still cant get my 95 K1500 chevy with tbi 5.7 to run right. It runs great cold but misses once warm and under load. Heres what I have done. New plugs, wires, cap, rotor, fuel and air filter, oxygen sensor, collant temp sensor and new ecm. I have swaped some parts of a running truck. Module under dist. cap, fuel pump, and map sensor. We have tested the egr. There are no codes and no check engine light. I have got a lot of good info and advice on here. Does any body have any other ideas? I am stumped.

Walt Davies · Sep 3, 2012

Check compression when cold and warmed up could a valve sticking.
Walt

bob15 · Sep 3, 2012

The temp sensor, did you change the one that goes to the gauge or the one to the ECM? Not sure sure on the 95's, but on the 1996 there were 2 different sensors.

Could it be a fuel issue?

Phil-mar Farms · Sep 3, 2012

Check ground wires,battery to body, frame and engine.

GeneMO · Sep 3, 2012

Fuel tank clean?

Gene

farmall300u · Sep 3, 2012

I would check the distributor for wear and then adjust to get it to run under load. Forget the specs, manually move the distributor until it stops missing under load.

rustred · Sep 3, 2012

coil???
valve adjustment?
dont tell your ins. that you burn't it.

Wayne in MN · Sep 3, 2012

I had a similar problem with my '02 pickup; it ended up being the catalytic converter on the right side was partially plugged. Truck ran fine until under load and would miss & loose power.
Have a tecnician use a low pressure gauge tester that will measure the back-pressure in the exhaust system AHEAD of the converter.
Too much pressure will cause the problem to occur.
Good luck.

John in Nebraska · Sep 3, 2012

my 96 chevy with 350 would stumble under load, finally got to missing at idle. Compression good all across. Found the intake manifold gasket had slipped, letting crank case air into cylinders 3 and 5, when apart the hard plastic gasket had sagged enough to see. I understand this is a 96 to 2002 problem, but maybe yours has a later engine?

Anonymous-0 · Sep 3, 2012

Have you checked for vacuum hoses or pots leaking? Take a can of starting fluid with you, when it starts acting up, start spraying a hose here, and there, one at a time. If the engine smoothes out, after you spray a certain hose, you found it. Also check for correct hose routing, there should be a decal under the hood, with the diagram.

Anonymous-0 · Sep 3, 2012

The one to the ecm.

Anonymous-0 · Sep 3, 2012

We also checked for vaccume leaks and changed the coil. Dont worry, its not insured for fire any way.

jamesinok · Sep 3, 2012

catalyic converter plugged on one side,both sides plugged will shut down to no power. I have had to replace on two GM products. James

da.bees · Sep 3, 2012

I lean toward John in Nebraska's thoughts about intake gasket leaking. If you are loseing coolant,that would also point to intake gasket.
I wouldn't bet on pulling codes from a 95 because, #1. Eventhough there is a port to plug into,if you compare it to a 96 and later vehicle you will note that not all the positions are populated by wire in the 95 and earlier. #2 The 95 OBD port is there primaryly for EPA related issues.

farmer boy · Sep 3, 2012

I am in no way an expert on this, but leaking intake gaskets was a Vortec thing. John in Nebraska had a 96 which would have a Vortec. 95 was still a TBI.

mike in new mexico · Sep 3, 2012

I bought a 98 chevy K-3500 truck and it would start great cold but after it would warm up I would have to lay on the starter to get it to run, ran great on the road but once it was hot it would not idle, I replaced about all the sensors I could find and still the same, then I took it to the dealer where a friend of mine performed a diagnostic for 50 bucks. He said that it was dumping too much fuel and that it had to be a defective fuel pressure regulator or defective fuel injectors. I had already replaced the regulator so I started looking at injectors and found a company in Canada that specialize in injectors and they described my problem to a tee. They sold me a rebuilt set of Bosch injectors complete with waranty for $200 including freight. I got them in within a week, installed them, and now my pickup runs as good as a new one. BTW, here the parts folks were asking over $700 for the injectors with the same waranty as the rebuilt ones I bought. I realize now that I spent several hundred dollars on sensors I didn't need.-mike

Gene-WI · Sep 3, 2012

I also have a "95 1/2 ton and it used to act up, put plugs wires and everything else I could think of, finally gave up and took it to the Chev dealer and asked them to diagnose the problem, ended up it was the egr and I went to the parts store bought a new one and installed it and has ran perfect ever since, best 100 bucks I ever spent. Gene

Iowawill · Sep 3, 2012

Are you aware that in order to time this engine that you must first disconnect a wire behind the glove box? Have you checked to see if the exhaust manifolds are glowing after driving for a while? My truck started running poorly after pushing snow last winter and it turned out that apparently the distributor was moved after ramming some snow and the motor was out of time.

Goose · Sep 3, 2012

Have you had it to a dealership or sophisticated independent shop and had it put on a diagnostic machine?

If not, why not?

As a refuge from both GM and Ford service departments, it never ceases to amaze me to see people put $500 or more in unnecessary parts on a vehicle instead of spending $60 to have someone put it on a machine and do it right.

David G · Sep 3, 2012

Why would you replace all those parts without diagnostics?

Anonymous-0 · Sep 3, 2012

Its hard to find a trust worthy shop in my area. I would crush it before going to the local gm dealer.

Bryan inIowa · Sep 3, 2012

Gotta be one somewhere. Ask for referals etc. Look how much time and wasted $$ in parts you have now ?

oldtanker · Sep 3, 2012

(quoted from post at 10:49:34 09/03/12) I am in no way an expert on this, but leaking intake gaskets was a Vortec thing. John in Nebraska had a 96 which would have a Vortec. 95 was still a TBI.

Any engine can develope an intake gasket leak, just some have intake gasket issues.

Rick

mite-help · Sep 3, 2012

well, i feel for you--i also have a '95, & own a very good obd scan tool. Diagnostic codes just flat don't come out like the newer obd11 system. only suggestion that i haven't seen here is dist. shaft bushing wear/side play messing with reluctor wheel clearance--ran into that once--might pop the cap & shake rotor. good luck--

Swamp Land · Sep 3, 2012

I had a problem with a chevy similar to what you described. Chevy dealer couldn't locate problem due to no light or codes showing up during diagnostic checks. Still cost 150 bucks. Old farmer said, son get you 2 bottles of lucas injector cleaner and put it in the tank and fill it up. 3 miles later problem solved, been putting a bottle in it now about once every 3 monthes.

Eugene Alt · Sep 3, 2012

My 94 sheared the pin on the gear on the dist tributor. Couldn't keep it in time and no power.
Gene

36 Coupe · Sep 3, 2012

Your method of troubleshooting never works.

Anonymous-0 · Sep 3, 2012

Goose, do not know where from but around here it's 150.00 for the scope and another $100.00 hr labor and it always takes 3-4 hrs the way my math adds up thats about $550.00 have not seen a $6o.oo mechanic in yrs sorry Have a good day Jer

cd1 · Sep 3, 2012

yep, the older ones had it, and it is a weird problem. when they go out it defaults to a really cold temp, maybe zero degrees? so its extra rich

Chris Jones · Sep 3, 2012

Only wanted to say that once I had a problem and a service tech replaced a lot of parts and said they thought it was better. It wasn't. I finally decided to try some things myself. Come to find out they replaced bad spark plug wires with bad spark plug wires. Yea, they did replace them as the ones they put on were a different color but the ones they put on were also bad. So just because something is replaced doesn't mean that isn't the problem.

JRSutton · Sep 3, 2012

If you have a parts truck - I'd swap coils.

504 · Sep 3, 2012

Check the cap again, look for tracking and moisture. There is a vent hole in the bottom of the disturber that gets plugged and the moisture will rise through the shaft when it warms up. If the cap is tracking pitch it and buy another. BTDT

CenTex Farmall · Sep 3, 2012

Check intake manifold bolts to see if all are tight. As others mentioned could be intake gasket leak.

Here's another one. Pull #1 plug and manually find top dead center. Compare with where mark on harmonic balancer is. IIRC your motor is timed at zero degrees static advance. Timing could be set off based on mark being in wrong spot.

Had one once where the outer ring had walked about 20 degrees or so. Dealer couldn't find problem. It wasn't obvious that the outer ring had walked. This was on sister's vehicle.

It can be frustrating troubleshooting newer vehicles.

Mike in Mn. · Sep 3, 2012

Sounds like you have a fuel problem, it's richer when cold and leans out when up to operating temp. Runs good cold and bad when hot. I would really check out the intake manifold gasket. and the brakebooster diaphragm for a vacuum leak. Has that engine have the vortec fuel injection set up. they gave a lot of trouble, but usually a flat miss. Drive er down the road with a fuel pressure gauge hooked up and see what the fuel pr. is doing. Do you live in the rust belt. Clean all the grounds!!!! I know your frustration, good luck.

Hay_Man · Sep 4, 2012

You haven't said anything about having to add coolant. So Maybe your OK on the gasket failure issue, unless its sucking air around the intake gasket. You can find those vacuum leaks around that gasket and other places with a spray can of wd 40 while its running at idle speed and warm. The engine will speed up if it sucks the flammable propellant at the leak site. Mine started using a lot of coolant (closed system shouldn't use any) no apparent leaks, finally developed a dead miss when warm, no pulling power. Cam was worn out from coolant in the oil. Leaking intake gaskets. Replaced engine with crate engine from GM. $1700.00.

Neb Super H · Sep 4, 2012

In my 92 5.7 the engine would surge just off idle at around 1700 to 2000 rpm if I stay at the range for a long time. I disconnected the EGR valve and capped that and the line. Runs great but will kick the check engine light. I have put new egr and gaskets on but it will still surge and cut out till I just cap them lines.

Good Luck!

I am going to burn my truck!

Well-known Member

Well-known Member

Member

Member

Well-known Member

Member

Well-known Member

Well-known Member

Member

Well-known Member

Well-known Member

Well-known Member

Member

Well-known Member

Well-known Member

Member

Member

Member

Well-known Member

Well-known Member

Well-known Member

Member

Well-known Member

Member

Member

Member

Well-known Member

Well-known Member

Member

Member

Well-known Member

Well-known Member

Well-known Member

Member

Member

Member

Similar threads