Topic: 1994 Toyota 4Runner dies on inclines ..... ? FIXED ! ! ! !

[79-TimberFaller]

So here is the story: a good friend just bought a 1994 Toyota 4Runner 3.0 v6 and she loves it... her only complaint is that it dies on inclines and declines....

So I rode with her to see if it was true...

We stopped on a steep hill and the engine bogged down started pinging and then died when trying to take off... felt like the engine was loading up

Then stopped on a decline and it started to search for an idle... going from 500rpm -1200rpm eventually it died on its own

Restarted it and idled like a champ... drove out of the drive way and 1 block stopped in the same place and it did the same thing...

runs great until you have to stop on a hill or a sloped driveway

No check engine light

Any suggestions?


Thanks

[lucky7]

wish i new fighting the same kinda problem dies at idle some times and has a miss no check engine light.
thinking about new injectors .you might think about new fuel pump & filter.

[jeepish]

Was the tank low on fuel?  I know that the gauge unit is in the back of the tank.  Going downhill, my 4Runner can read empty.  Then on flat ground 1/8 tank.  Uphill, nearly 1/4.  The gauge is clearly reading off the back of the tank.  If the actual fuel pickup is located in the middle and you are on a decent hill and low on fuel, it might putter out...  Just throwing out the obvious.

[93tonkatoy]

Are you not having any problems on steep grades if you keep moving (climbing a long hill)? I don't know what you have looked at yet, so, I will tell you what comes to mind.

You might have some water in the fuel (low fuel level will aggravate this because it will move around more).

If it dies while you are holding the brake, check your vacuum booster. may be a bad diaphragm. either disconnect the booster and plug the line, or park it on level ground and press the brake HARD while it is idling. see if it dies. Or, stop on a decline and set the e-brake quickly and let off the brake. If it still dies, then the booster is not the problem, and i would look for loose or shorting sensor wiring/plugs.

Also, check your idle speed, and the adjustment of your TPS. When it is searching for an idle, did it sound like the ignition was shutting off, then coming back on, repeatedly? If so, i would definitely check the tps.

That's all I can think of off the top of my head. If you have time to study, look through the fsm diagnostics: http://personal.utulsa.edu/~nathan-buchanan/93fsm/

[BLACKDOG]

Was the tank low on fuel?  I know that the gauge unit is in the back of the tank.  Going downhill, my 4Runner can read empty.  Then on flat ground 1/8 tank.  Uphill, nearly 1/4.  The gauge is clearly reading off the back of the tank.  If the actual fuel pickup is located in the middle and you are on a decent hill and low on fuel, it might putter out...  Just throwing out the obvious.

fuel pickup is in the center of the tank   This could be the problem, but I doubt it.  Unless she is on E, there is enough fuel in the tank to keep the truck running on an incline.

[79-TimberFaller [OP]]

Most Recent event with the Runner...

taking off from a light engine warm she felt a surge .. she described it as a loss of power for a second and then back to normal .. it did it 2 times ..

Nice i didn't think about the brake booster .. i will look into that ..

as for the fuel tank level it has done it before on half full and 1/4 tank..
that is actually the first place i looked fuel level ... had a car with a dirty fuel pickup sock (filter) with a tare at the top.  ran great but if you ran it below a 1/4 tank it would not run at all or if you we going up a long hill and the fuel would not reach the tare it would starve the engine of fuel which surged and sloshed fuel .. crazy  .. thanks guys for the input i will let you know what i find ..

[79-TimberFaller [OP]]

Alright i finally got this figured out .. i had the car all day and it took me about 20mins to figure it out hahah

so..

The FIX

When on a hill there was alittle flex in the motor mounts which rocked the engine backwards.. causing a huge vacuum leak after the MAF (mass air flow sensor) and since someone before had the stock airbox removed and installed a K&N kit i could not hear the leak ..



This was after i fixed the problem haha

The culprit was the K&N setup: The K&N was bolted to the fender well and was not at the right angle .. so when the engine rocked back it pulled the intake boot part way off the K&N tube.. which caused the leak.. drive on level ground closed the gap ran like a top ..

sad thing is i tested everything before i found this out haha.....fuel pressure perfect.. TPS workin...

alright hope this helped lucky 7 ... it fixed my problem
 but i would also look for tares in the intake boot ..

[lucky7]

cool i'll check that but i haven't messed with my air cleaner but i'm gonna get out my starting fluid and start
spraying.