ser91

first let me start by introducing myself as i am new to the forum... my name is Sam and i live in Cincinnati, OH and i just recently purchased a 1994 Pickup extended cab long bed v6 4x4 5-speed... i went to pa to get the truck thinking it had a blown radiator, well the HG were blown so i ended up getting the truck for $200... so no complaints at all!

i put new head gaskets on with a full gasket set and all that jazz... cranked it over the first time and it started right up... so it runs fine and stayed at a good temp and all is well... i drove locally stop and go for about 130 miles over a few days to make sure everything was good to go... no problems minus the fast that the cat fell off...

then........ i pack the truck up to move to cincy from cleveland and hit the road... i drive continuous for about 120 miles and stop at a rest area for a restroom break... truck ran perfect the entire time with cruise set at about 70 the whole way...

i get back in the truck and go to start it and it cranks, runs for about 2 seconds up to about 700rpm then stalls right out... crank it after it stalls and it just cranks... if i primed it a few times it would start and stall again the same way... well after beating the gas tank and checking obvious cause such as fuses, no luck... i primed it over and over again it it started, after about 45 seconds it just cut out... finally kept trying and priming and then the battery had a loose terminal so it just clicked... i jumped out snugged it up went to start it and it fired up and i just kept driving until i made it to the new apartment... as soon as i get here and in the lot, it stalls again once it started to idle...

so then i tried for about an hour to start it and tap the tank, i don't have tools with me yet... no luck at all and it didn't even come close to trying... i go outside today and it fires right up on the first try... drove about 10 minutes to the store and it died as i was parking... tried to start it a couple more times and nothing at all... so i went in the store for about 20 minutes and came back out and once again, it fired right up... drove it back to the apartment while making sure to give it throttle at all times and not let it drop to idle... i pull in and as soon as it drops to idle it stalls... and now won't start...



sorry about the huge post, just figured i would give as detailed description as i could to clarify the problem...

so... fuel filter seems ok... it was getting plenty off pressure 400 miles ago when i did the head gaskets... injectors all looked ok at the time of the repair...

the only other problem i could think of is that maybe the fuel pump/fuse/relay are getting too hot after long drives...? and now after the long drive it is just about done...? the relay is hot to the touch when it won't touch, but nothing that seems too abnormal... the truck does have 294k on the body and i am not certain of the mileage on the pump, but the previous owner said he didn't change it...

please if you have any suggestions about what could be causing this let me know... i am a mechanic and can try out anything, so don't be afraid to throw it out there...

and i did search and couldn't find a clear answer for my problem...

thanks, and yota tech is an amazing forum!

-Sam

xxxtreme22r

now that's a good detailed first post asking for help.

Sorry can't help you too much though the the 3.0 so good luck. I am sure someone will be willing to help you out here. Lots of great guys here willing to help someone out.

ser91

it sure seems that way! i've browsed the forums many times as i have had a 94 2wd v6 pickup for many years...

and thanks about the details, i hate when people just post up "my truck keeps stalling, what do i do?" lol

-Sam

thook

So, it doesn't start at all, now? No running problems, just starting?

It's either not getting fuel or spark.....or both . Try to determine which one it's not getting.

There's fuel pump testing terminals in the diagnostic port labeled FP and B+. Short them with a wire and try and start it. This bypasses the pump switch in the AFM and the pump relay.

As for spark, you probably already know to just pull a plug while connected and ground it to check spark?

ser91

i'm going to try that once i run it again and then it stalls...

and it's getting spark still....

it will start once it sits, and then after is stalls out it will just crank... but if i prime it multiple times and try it, it starts up to about 700rpm then stalls instantly after about 2-3 seconds of running...

thook

Is it sitting long enough to cool off much, or are you trying to start again (with starting success) while the motor's still hot? I'm trying to determine exactly how it's temp related.

Was there any running problems before it finally decided it didn't want to start anymore?

ser91

the first time it stalled at the rest area after 120 miles, it sat for probably 35-40 minutes before it finally started... that was me trying just about the whole time... so the motor was still warm

same with today at the store, it was warm when i tried it after shopping for 20 minutes and started up... but immediately after it stalled i tried it and nothing, which is why i let it sit while in the store...

and don't think it's engine temperature related, more electrical temperature related... the electrical system cools off much quicker such as the fuse, relay, and the pump itself...

and the truck ran perfect before it started happening... like i said, cruise set for 2 hours straight without a hiccup... then i parked at the rest area, turned it off and everything seemed normal until i went back to the truck to leave...

thook

After reading again, first thing that comes to mind is the coolant temp sensor. But, there's a few other possibilities, as well.

http://personal.utulsa.edu/~nathan-b...63troubles.pdf

hermyboy3000

I had a similar experience like that with mine, turned out my VAF was starting to fail. I swapped it out and that solved my problem. If you have a FSM you can do the simple test to see if that's it.

Good Luck

thook

True. So, try shorting the fuel pump terminals. If it'll start, see if it will continue to run without stalling.

Cpt_Buckout

I have a 1991 Toyota pickup and it's doing a similar thing. The longer it runs the idle seems to be at lower rpm and rough. Like yours when I bought it and drove it home three hours everything seemed well. Then several days later it seemed to take longer and longer to start and then it wouldn't. If I prime it, it will start and run, but if I drive it any distance it might start and then take longer to start and then won't unless I prime it. I need help as well and this sure seems like the place to find it. I was going to change the fuel filter but can't locate it. Checked the frame and under the hood? I did replace the fuel pump and it didn't help the starting situation. Sorry to jump on your thread but out problems seem to be similar. Thanks Junior

Cpt_Buckout

P.S. What's the VAF?

thook

The filter's on the pass side of the motor right near the starter.....to the right of it as you're facing it. Remove the access panel underneath the pass side wheel well and you'll see it. The panel has 4 10mm bolts. You'll see it above and behind the tire. Anyway, pull it off and look. You'll see the filter. Might help replacing it, but it might not. They're cheap enough, so no hurt.

VAF is volume airflow meter. Or, AFM or VAFM. Some called it MAF sensor, but those are somewhat different animals on newer vehicles. Newer than '95, atleast.

http://personal.utulsa.edu/~nathan-b...33volumeai.pdf

myyota

Three things come to mind, the AFM, core relay, or the fuel pump. Like thook said, try jumping the fuel pump and see if it starts and runs, and then go from there.

ser91

Thanks for all the ideas... I'm currently still stuck as to what it may be, only because the problem has gone away recently... I've just been driving and letting it idle to try to make it stall out... then I was going to manually open the vaf to make sure the really isn't overheating... then I wad going to jump the pump... I already ordered a new pump and it will be in on Tuesday... so that will be replaced for sure... I'm just hoping to properly diagnose it rather than hoping that was the problem...

I definitely appreciate the input from everyone! Thank you!

Cpt_Buckout

Here's the update on my 91. Hope this helps and still don't know is wrong??? I can prime it by pouring fuel into the throttle body and it starts and runs. I've changed the fuel pump and fuel filter. I drove it to town and left it running everywhere I went and when I got home and killed it, waited awhile and then tried to start it and this time it started? About the last five times I have drove it and killed it wherever I went it has started? It was turning over and over and had to be primed to start but would run and not die after starting it? So far it has started everytime, only two times after the fuel filter was installed did it not start. Now it seems to start every time. I let the seat belt buzzer time out before I try to start it and turn the key and let it go and it starts? I thought it was the fuel pump at first but if it was primed it would start and run so I figured it was not the fuel pump. I'm sure the problem is not over and still have no idea what the problem is? I hope this helps someone out but still have more to do I expect. Thanks to all for the replies, emails etc. and sorry for jumping this thread. Thanks Junior

xxxtreme22r

maybe the fuel pump relay in the fuse box?

Cpt_Buckout

Thanks xxxtreme22r.

ser91

sorry about the delay everyone, i've been out of town without the truck for a while...

but, i put a fuel pump in and the problem is gone... i've put probably 900 miles on it and drove for a couple hours straight while stopping in between and no problem at all! thanks everyone for the advice and i'm glad i got it fixed!