1989 2.9L sputtering under load

[nickel]

hey i have an 1989 ranger 2.9L v6 that has a sputtering problem that i cant seem to sort out or fix...

it started after a trip from Vancouver to Kelowna over the weekend. I was climbing up the pass out of Merritt, just chuggin along in 3rd @ 4000rpm for awhile... i didn't keep an eye on the temp as i should have been. The temp got real hot and coolant was boiling over out of the overflow container. Stopped to topped up the coolant and let the engine cool a bit. Drove home back to North van fine.. nothing wrong.

Once i got back to the city driving i started noticing that when my truck got to operating temp that it would start missing and the truck would start hopping when under moderate to hard acceleration or driving up hill (under load).

Today I replaced cap, rotor, plugs, & wires. Ran compression test on all cylinders and they were all around 150-155psi. The plugs that came out were normal discoloration/wear. Timings good - i run 12deg BTDC and have for as long as i can remember. The engine is a rebuild from Canada Engines and has about 30 000 Km. O2 sensor was replaced about either a year or 2 ago .. don't have my repair log with me at the moment. Nothing helped with the sputtering.

After replacing all those parts today drove for about 30KM the truck got real hot again and coolant was boiling over. I got the engine cooled down and pulled the thermostat so the coolant flow was more continuous through the block. That didn't seem to help.. also now the sputtering happens more regularly, and even started to idle rougher.

I have a leaking either # 1 or #4 injector.. which has been leaking for awhile now & clutch is on the way out has been for a couple weeks.. so i dont think these would cause this issue all of a sudden.

Oh and there's NO white smoke coming out of the tailpipe at any time.


Any suggestions on what might be the culprit would be much appreciated!

tomorrow i'm going to check the oil cap & dip stick for any good build ups

 

[jhammel85]

Hmm...It sounds like you've hit everything that I would look at.

When it gets hot, is it ALWAYS when it is under load (like the climb you talked about)? I'm wondering if maybe the radiator is partially blocked.

As far as the missing, that's a tough one. I would fix the injectors to make sure that they are in good working order before looking for any other reason.

 

[nickel]

this morning went to test the truck out.. turned over, started perfect... idle was perfect.. as soon as gave it gas to drive it feels as if the truck is wanting to stall out. Had to play with the clutch & gas to get it moving. Now at any temp after i give it gas to accelerate it'll sputter & hop.

If i'm stopped at idle and in neutral or clutched in and go to gas it, the engine hesitates and bogs before the engine revs up.

theres no build up on the oil cap. there were a few metal shavings on the dipstick. So I drained a bit of the oil today to see if there was any contaminates but nothing.. Still at a loss. Going to try changing the fuel filter see that helps any.

 

[silverranger88]

help

not sure if the 89 2.9L has a coil but I have an 88 and it was doing the same thing yours is. I threw in a coil and its been running great since

 

[Powerbrapp]

I'm having the same problem a bit.
it doesn't do it when cold only at operating temp. but under load around 1500 to maybe 2300 rpm it hick-ups.
i was talking to some of my buddy's and they say the 2.9l had bad fuel delivery system. like the fuel pump relay and fuel pump

check your spark plug wires and plugs at night on a dark road at operating temp, i was checking out the engine bay on the logging road, and on all 6 spark plugs/boots. where all sparking off the block past the spark plug boot.
put some dielectric grease on all the spark plugs and on the cap boots still did'int help but i haven't had time to see if it was still doing it

Im thinking it might be the computer on the back of the distributor that's doing it, had lots of problems with them being sensitive to heated or when u get water/moisture in there.
that computer controls a'lot of stuff spark, rpm gauge, injectors and i think fuel pressure

im gonna try and relocate that computer but i think u have to pull the distuputor to get it off "have to drill it out i think" and see if it helps and i will let u know

 

[Powerbrapp]

I'm having the same problem a bit.
it doesn't do it when cold only at operating temp. but under load around 1500 to maybe 2300 rpm it hick-ups.
i was talking to some of my buddy's and they say the 2.9l had bad fuel delivery system. like the fuel pump relay and fuel pump

check your spark plug wires and plugs at night on a dark road at operating temp, i was checking out the engine bay on the logging road, and on all 6 spark plugs/boots they where all sparking off the block past the spark plug boot.
put some dielectric grease on all the spark plugs and on the cap boots still did'int help but i haven't had time to see if it was still doing it

I'm thinking it might be the computer on the back of the distributor that's doing it, had lots of problems with them being sensitive to heated or when u get water/moisture in there.
that computer controls a lot of stuff spark, rpm gauge, injectors and i think fuel pressure

I'm gonna try and relocate that computer, i think u have to pull the distributor to get that computer off " have to maybe drill out the screws

 

[daduke]

you don't have to pull the distributor. they sell a tool for it its just 2 really deep set in tiny screws. really easy to change and they do get really weird if you get them too hot.