2.9 after everything that I've been through still nothing.

Try this: crank the engine for 10 seconds (without starter fluid). Assuming the engine doesn't start, remove a spark plug and inspect it. Is it wet? Does it smell like gas?

If it does, do a compression test. If it doesn't, you still have a fuel issue. Maybe the fuel pressure regulator?

O2 sensor?

sexybluelady said:

Nothing is blocking the air intake. I have the tb open right now (took the intake pipe off). I have spark I haven't checked compression in awhile. But here's the thing, it was running just fine, with the help of starter fluid a few weeks ago, sounded healthy and idled great. After I replaced the AIC, then whatever was in my fuel lines from sitting for years clogged up the FPR and then the injectors once I replaced the FPR.

I put the new injectors in the truck and just finished checking my timing which is spot on, and still nothing. I'm at a loss right now.

Click to expand...

I pretty much went down the same road as you with my 88 2.9, but in addition, I pulled the cat as it was badly plugged. Still had starting problems and discovered the high pressure fuel pump was cutting out. I replaced the O2 sensor and that cured it.

Anyone have any ideas? That has READ all of the things that I have already done and what my symptoms are? I have a video of trying to start the truck. Sounds strong just won't start.

Again for those that skip the first page. I have fuel pressure, I have spark, I have compression. diz is good, TFI is good. no cats straight exhaust, standard 5spd. No TCU ECU!

If you have:
Spark, at the right time
Fuel, in the correct mix with air
Compression, above 120psi

Then a gasoline engine will run, just physics
So one or more of those three isn't what it appears to be after testing

1988 computer will use Batch Fire injection, on a V6 that means computer will open 3 injectors at the same time to keep intake full of air/fuel mix, and it just alternates between the two sets of 3 injectors, so not sequential fuel injection, one step up from carb, just FYI.

You didn't mention compression numbers?

Spark is fairly easy to test for if you have compression.
50/50 test, which is what you did by spraying fuel into the intake
If engine starts and dies, then a fuel issue
If engine doesn't start then spark issue(or compression)
50/50

If no start then I would run a jumper wire from battery positive to Coil "+", hot wire.
This eliminates the two power pathways used on the coil power in 1988
If engine starts then wiring problem, could be ballast resistor, or ignition switch

Also put your hand over intake opening while someone cranks the engine, should build up a vacuum sucking hand tight, or you can use a vacuum gauge, 3-5" of vacuum should build up while cranking, throttle closed.
If it builds up then starts dropping exhaust is clogged, air can't be pushed out so new air can't be sucked in.
Gasoline engine is a self powered air pump, so vacuum gauge($20) is a very good tool to have in the box.

Distributor, pop the cap and crank the engine, make sure rotor is turning.
Now try to manually turn the rotor, it shouldn't move of course, I have had drive gear roll pins shear off, so distributor comes out of time as soon as you try to start engine, lol, and you still have good spark just out of time.

Firing order, have someone else check it, lol, I can't even count the times I have known for a FACT that the firing order was RIGHT, FOR SURE 100% RIGHT!!!, and it wasn't

Yes, after cranking engine check one or two spark plugs, should be WET with fuel.
But no start on 50/50 test would indicate spark issue not fuel issue

What does "No TCU ECU!" mean?

Have gone through exactly what you have, however I don't see where you've ever changed the O2 sensor....it is part of the fuel delivery circuit. If you haven't replaced yours yet, give it a try..before you torch the thing. You are this far in to it, what do you have to lose?

RonD said:

If you have:
Spark, at the right time
Fuel, in the correct mix with air
Compression, above 120psi

Then a gasoline engine will run, just physics
So one or more of those three isn't what it appears to be after testing

1988 computer will use Batch Fire injection, on a V6 that means computer will open 3 injectors at the same time to keep intake full of air/fuel mix, and it just alternates between the two sets of 3 injectors, so not sequential fuel injection, one step up from carb, just FYI.

You didn't mention compression numbers?

Spark is fairly easy to test for if you have compression.
50/50 test, which is what you did by spraying fuel into the intake
If engine starts and dies, then a fuel issue
If engine doesn't start then spark issue(or compression)
50/50

If no start then I would run a jumper wire from battery positive to Coil "+", hot wire.
This eliminates the two power pathways used on the coil power in 1988
If engine starts then wiring problem, could be ballast resistor, or ignition switch

Also put your hand over intake opening while someone cranks the engine, should build up a vacuum sucking hand tight, or you can use a vacuum gauge, 3-5" of vacuum should build up while cranking, throttle closed.
If it builds up then starts dropping exhaust is clogged, air can't be pushed out so new air can't be sucked in.
Gasoline engine is a self powered air pump, so vacuum gauge($20) is a very good tool to have in the box.

Distributor, pop the cap and crank the engine, make sure rotor is turning.
Now try to manually turn the rotor, it shouldn't move of course, I have had drive gear roll pins shear off, so distributor comes out of time as soon as you try to start engine, lol, and you still have good spark just out of time.

Firing order, have someone else check it, lol, I can't even count the times I have known for a FACT that the firing order was RIGHT, FOR SURE 100% RIGHT!!!, and it wasn't

Yes, after cranking engine check one or two spark plugs, should be WET with fuel.
But no start on 50/50 test would indicate spark issue not fuel issue

What does "No TCU ECU!" mean?

Click to expand...

Hiya, sorry I never got a notification that anyone replied back to my post.
My bad TCU in the import world, just a lazy word for transmission computer unit. just letting people know that I do not have a Auto.
All of my cly had compression above 120psi, didn't list it because it was good back when I did a compression test. I've been jumping it or rather starting it with my remote starter switch. While testing it to see what was going on with it.
Oh also I hooked up my vac gauge while I was diag my motor many moons ago when I had did a compression test, leak down test, and my ohm meter was my best friend. Nothing was out alarming so I didn't write it down. I have a three bay rolling toolbox(s), no need to worry, I have just about every gizmo under the sun in that thing. Most women buy shoes, I choose to buy tools and stay dirty.

Update however. I did my timing again for the 100th time. Still ran like shit. So I decided to sea foam the crap out of the motor. Don't know why I didn't think about it before hand, since it had been sitting for years. Put a can in the fuel tank with a full tank of gas. some in the crankcase. The ran a can through the intake. Then drove it for awhile. The ran a can of the seafoam intake cleaner through the intake again, let it heat soak for about 20-30 mins. Then ran it hard again and did a oil change. And my oh my, seafoam did the trick. It not longer sounds like a dying diesel bus. Starts up from the ign key just fine. After everything that I did to this thing, rebuilt the entire top end, replaced my timing chain, before I went off to school to start a new, new, career which ended up being just a waste of money and time and more debt. It turned out to just be gunk in her trunk.

Oh I also changed out the air charger temp sensor, tested it with my OHM meter and it was a little out of spec so I said WTF not. And it looked like shit! after cleaning out who knows how much gunk was caked up in my motor. Also replaced the IAC, MAP since I have lifetime warranty. Didn't have to, but free is free and I didn't care. So, eh. Why wouldn't I.

I still, have to take care of my exhaust leak, that I have at my header and rear muffler. It's killing my the little hp that my truck does have. I'll pull out my MIG and weld up the holes next week.

Also have to change out my front wheel U-joint. Dana 28's you know how they are. Sigh....

Beside that and a few little things like fixing my CB radio and hooking up my extra led reverse lights. It looks like my little POS baby is good to go.

I swear, I just sat in my truck and listened to it run for half a day. It was like seeing a old lover, good times, good times.

Thank you for your help everyone. I hope this thread helps out someone else in the future.

Bulwapo said:

Have gone through exactly what you have, however I don't see where you've ever changed the O2 sensor....it is part of the fuel delivery circuit. If you haven't replaced yours yet, give it a try..before you torch the thing. You are this far in to it, what do you have to lose?

Click to expand...

O2, tested out good, so I wasn't going to throw parts at it, that were good. And it was changed before the truck sat.

Glad it all worked out well.


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