Hey Guys, just wondering if anyone has had this issue before. I attemped a tune up on my 89 pickup with 3VZE 3.0. I replaced the valve cover gaskets, plenum gasket, spark plugs, wires, pcv valve and pcv hose, throttle body gasket and cold start gasket. I also put on a short ram air intake while I was at it. However, now it only wants to run for about 3 minutes and then it starts to sputter and die out. If I attempt to start it up immediatly again it will only run for about 30 seconds and then die. If you leave it for a while (few hors or overnight) it will do the same thing...run for about 3 minutes and then die out again. I have put back on the factory air intake and the same thing is happening. I also tried taking off the positive battery connection for a bit. I am stumped, any help would be greatly appreciated. Thanks

 

*should be hours not hors. Also it is not showing any check engine or other lights on the dash.

 

My guess is a clog in the fuel system (most likely the filter, that's what it's for. But it could be anywhere.)

The right diagnosis is with a fuel pressure gauge. Of course, you're almost certainly due for a new fuel filter, but replacing it is, well, non-trivial. https://www.yotatech.com/forums/f116...ctures-218962/

 

Thanks, It was running fine right before I did the work. Would it just be a coincidence that it clogged immediatly after or would replacing the items that I did cause it somehow? Just can't see how that would happen at the same time.

 

I will replace the fuel filter and see if it helps, thanks for the link

 

is a short ram intake another name for a cold air intake? if so, try re-installing the factory setup and see how it does. the air flow sensor may not be happy with it. when it is running, does it idle smooth? i'd say its a self inflicted wound, possibly even bad parts, but should be easy to figure out and repair.

 

Yes it is a cold air intake. I have already installed the factory system with the same results. It starts off with a low idle for about 2 seconds and then jumps up to 1200 or so and then settles down to around 1100 for the duration of the 3 or so minutes. I gapped the vpower spark plugs to .31 and used ngk wires. Is it possible that a vacuum leak could be causing it? Thanks

 

I would double check all of the vacuum lines that are on the pass side of the plenum. it is possible one of them is crossed up. I doubt it is a fuel or spark issue.

 

a vacuum leak will cause a higher idle, but that wouldn't cause the truck to sputter and die and not want to restart. still would be a good idea to check for leaks, and check to make sure the right hoses got put back in the right spot. will it get to a point where it won't start or run at all?

 

I just did the plenum "flip" so except for the large breather hose at the back and the PCV hose being replaced none of the other hoses on the passenger side were touched. I removed the EGR but that has been screwed back on. It gradually gets less and less likely to start. If I were to go start it right now it would run fine for about 3 minutes, then if I were to try to start it again it would run for about 20-30 seconds at a lower idle struggling and then die out. I havn't attempted a third time yet but I imagine it would be even less. Thanks for the help guys. I'm going to check the vacuum lines again just to be sure.

 

if you can, get it to a point to where if won't run at all. then check for spark to see if its an ignition issue. if you have spark, use some starting fluid and see if it will run indicating a fuel issue.

 

Okay, thanks for the help...it is greatly appreciated

 

The consistency of it points to something that is happening by design, such as a engine heat activated vacuum port opening and creating a vacuum leak. You say the EGR has been put back on. Are you CERTAIN it isn't being activated? What it sounds like to me is a heat activated control opening and activating the EGR, or creating some other vacuum leak. Then when the thing sits for long enough the control closes again until you run the engine again.

 

Maybe I missed something, but does it just not want to idle, or does it not want to run at all? First time I did my head gaskets I mixed up the EGR vacuum line with a different one and it idled like crap, but would run just fine at higher rpm. Traced them down and hooked em up to the correct port and it ran like it should.

 

he said he left all that stuff connected so nothing should be hooked up wrong. but hell remove the vacuum line from the egr valve and see what happens, quick and easy to rule that out.

 

Thanks guys, it will run..I labelled and color coded all of the vacuum lines but I will double check to make sure. Wireguy, I'm not certain that it is not being activated. Would there be a way to test that? Thanks

 

To test the EGR just pull off and plug the vacuum line from the EGR valve, like oldblue says. Quick and easy test to find out if it's EGR related.

 

Thanks, I removed the vacuum line to the EGR...it acted a little different but still stalled after 3 or 4 minutes. It started the same beginning with a low idle of around 500 rpm for a rew seconds, then jumping to 1500rpm for a few seconds before settling in at 1000 rpm for 3 or so minutes. However, this time before it died it idled it around 500 for a minute or so, then jumped BACK to 1500-1000 before it slowly died out again. Not sure what to think of that?

 

try removing the egr valve completely and see how it runs. you'll have to block off the hole in the intake, your thumb should be able to plug it up.