Wesley Wood

I have a 1987 3VZE that is having some sort of fuel issue. The problem is not progressive, but I have yet to be able to identify exactly what's causing the problem.

Before I go into the strange actions of the truck, here is a list of what has been completed already:

9/9/2012 6 Ignition Wires & Coil Wire
9/10/2012 4 Tires - Jetzon Innovation 235/75R15
9/10/2012 2 Rear U Joints
9/12/2012 6 Quarts 10W30 & Filter
9/12/2012 Front Driver Side Axle
9/15/2012 6 Spark Plugs, Distributor Cap, Distributor Button
9/30/2012 Front Passenger Side Axle
9/30/2012 2 Front Anti-sway bar linkage
10/17/2012 Fuel Filter
10/19/2012 O2 Sensor
10/20/2012 Clutch Slave Cylinder
1/20/2013 New Battery Terminals and Grounding Strap

I know a lot of the above is not going to be related, but it needed to be done.

The truck is acting like it is starving for fuel at particular times.

When I start the engine from cold it idles fine, but when I put it in gear and give it gas it starts to bog down, sometimes to the point of stalling. This is GREATLY enhanced by cold temperatures. The colder and wetter it is outside, the worse the problem is.

If the vehicle does stall, it is almost impossible to get it restarted without letting it sit for some time. Almost like it's flooded.

When I do get it started and the outside temp is not to cold, the truck will start to get power once the rpms go over the "hump". I don't know how else to describe it other than it struggles then makes it past a certain RPM and starts acting like it should.

Once the engine warms up, it runs like it always has.

The second issue, which I suspect is related, but may not be, is that the truck under load does not seem to have enough power.

I can be driving 55 in 5th gear, but going up even a gentle grade with my foot on the floor will cause it to start slowing and eventually I have to down shift.

I live in the mountains and there are certain hills that I can not make it up in 2nd gear. I have to go to first.

This is the interesting part.... When I am in 4 low I do not have the hesitation. Even when it's cold. It's like the gearing is putting less load and keeping the rpms up.

I'm sure this is all clear as mud, but any help would be greatly appreciated.

I do not have any check engine lights or other indicators that something is wrong.

Thank you in advance

Co_94_PU

iTrader: (-1)

Inspect EGR, TPS, and VAFM systems. Check idle and timing. Check for stored codes in the computer, they don't all turn the light on.

Gamefreakgc

I second timing issues for the loss of power when warm. The V6 should be strong enough to handle what you drive on. I live near the Sierra's and the only time I have trouble going up a mountain is when I have 4 people in the cab, carpet kit, camper shell and a load of camping gear in the back.

The issue with the RPM's... I had that. Turns out it was a bad ECT (Engine Temperature Sensor). I also had low compression in a cylinder so if you can, do a compression test or take it somewhere that can do it for cheap. The place I went to did it for free when they were doing some other work on it I wasn't able to do.

For the cold starts... check the VAFM. The internal temperature sensor (forget the name) might be going bad. I believe you'll want to check the E2 and THA circuits, use the FSM for the correct reading based off the outside temperature.

scope103

You could have a Cold Start Injector stuck open (which, as you hint, is flooding the engine. Then making it run rich, until the rpm is high enough to out-run the extra fuel). If you disconnect the electrical connector on the injector and that clears it up, your problem could be the cold-start-injector timer. But if the injector is just stuck open, that electrical test will make no difference.

But you need to do your diagnoses in order of difficulty. Check for stored codes (free), timing and compression (so cheap there's no point begging someone to do it for you). All as suggested above.

Patriot

Its a real funny thing.. but I too have the identical problem with my 22re. I have no problem starting it.. the Idle is perfect when hot or cold but no power till 3000 RPM then all of a sudden I have to let up off the gas because its accelerating to fast!... then up-shift and nuthin... no power... no go!...Almost "flat" feeling. It is also apparent that it is intermittent for a few miles at a time... of course it happens mostly when you really... REALLY don't want it too.. like trying to merge on the freeway.. ahead of a dump truck!!!.. this thing is pissin me off!.. But what I have noticed is that when it is about to do it.. the aftermarket tachometer.. sunpro... will begin to bounce a little..like 300 RPM for a split second.. then... here we go!. Well hope you find your problem.. myself.. I think I'm gonna find a long drive off a short cliff (kidding)..actually I'm going to go replace my frigging alternator... cuz it just quit today!!! oh..and why does the brake light stay on with the battery light???.. inquiring minds want to know!

TNRabbit

Something else to consider; sounds like you might have a low fuel pressure condition OR clogged fuel filter, injectors, etc. Have you checked for ECU codes yet?

Wesley Wood

I will check all of the suggestions above. Thank you everyone. I have check for codes and have nothing

Some new information that may help though....

I stalled the truck as a result of the conditions I described. I tried restarting and it just wouldn't start up. It would sound like it was going to, but then immediately sputter down and keep cranking. I went on with this trying various things for about 20 minutes with no success. Eventually, I pulled the EFI fuse and turn the ignition on. Replaced the fuse and the truck started immediately and idled fine.

Co_94_PU

iTrader: (-1)

test the oxygen sensor, and monitor the A/F ratio, you can also by-pass the oxygen sensor by putting the throttle to the floor. Sounds like learned fuel mix problem.

TNRabbit

Just to make sure, you DO know that there can be stored codes with no Check Engine Light, right?

Wesley Wood

I had no stored codes.

Advancing the timing to 12 vs 10 seemed to solve most of my power issues. I have read over these forums that is a "common" adjustment to get more power out of the vze.

I am also getting ready to swap my fuel pump based on a consensus from every mechanic I've had look at it and here.

I'll let you know how it goes.

Anybody have a vote for drop the tank vs lift the bed?

Terrys87

iTrader: (1)

On a pickup, I strongly suggest tilting the bed. Remove the bolts on passenger side and loosen the bolts on the drivers side. You can remove the whole bed if you want. The fuel lines do not have much slack and trying to drop the tank and remove the hoses is a pain in the rear. Also some of the bolts holding the tank will most likely be rusted and snap on you.

Might want to check your tank and lines as well for build up in them. Be gentle on the metal line to the fuel pump assembly. Sometimes it is frozen and is easy to twist the metal line. Trying to find a replacement is getting harder to do.

Wesley Wood

Rust? On my truck? Ha

I have heard most suggest lifting the bed. It being December and having a gravel driveway to deal with (My 86 Chevy is currently renting the garage) I think I will give it a shot.