JEDI87

I have been having problems with my 91 4runner 3.0 not starting after driving,shutting it off for about 15-30 minutes.I just got a call from the dealer saying it was vapor locking and he had never seen one do that.He is trying to get ahold of toyota to get their input.Any ideas on what would cause that?

mt_goat

I don't know in this case but as a general rule don't put too much faith in what a stealer tells you.

JEDI87

They're telling me that they don't know what it is and they called toyota and they said it is bad gas,BS!I fill my other cars up at the same place and they're starting.I yelled at them for charging me for a cold start injector because they said that was the problem and it wasn't.Now they're "running more tests".

Bumpin' Yota

hmmm if you had a 6.5L chevy turbo diesel I'd tell you your PMD was bad. (pump mounted driver) But it's not any such engine....

It's definately something heat related however....

Now that I think about it, one time I let my truck idle for a good hour or 2 with the AC on in the hot summer sun down here and it did not indicate that it was overheated at all. However when I shut it down then went to restart several minutes later it wouldn't even engage the starting solenoid! After a few minutes she fired right up though. I have never had a problem since and that was a GOOD 5-6 years ago.

86toyota

I always thought Vapor lock was caused by a bad fuel cap

Bumpin' Yota

I thought vapor lock is that feeling you get when your girlfriend tells you she's preggy.......

lol

ttt

drkgypsy

Vapor-lock on the 3.0 is caused by improper sealing of the gas cap. Been there.....fix'd that. This happened a month after the truck was bought new from Hamer Toyota. Now, ya wanna talk 'bout stealerships......lol

ChickenLover

Yeah, check the gas cap for sure. Another cause of vapor lock is when your fuel lines get too hot and the fuel vaporizes before it gets to the engine, leaving an air pocket in the line. I really don't see how this could be the case unless you have modified something resulting in a fuel line being closer to a heat source.

The fact that you live at 6,200+ ft doesn't help either. At high elevations gas will vaporize at a lower temp.

JEDI87

If I have spent all this money for it to be a bad gas cap,I am going to be pissed!It makes sense though,We went to the store the other day and my wife drove and when I got out of the truck I walked past the filler and I smelled gas.They are testing the fuel pump and such now.Since I made a big scene about them not fixing it right the first time,they aren't charging me.I haven't modified anything.It just started doing it a couple of months ago but off and on.Now it does it everytime.

Bigblock

it aint vapor lock and it aint the gas cap.fuel pressure is about 45 psi,cant vapor lock that high.better check the fuel cut relay,or simply the fuel filter.filter fixed mine when it did this,also increased engine power.

JEDI87

I just talked to the dealer and they said I have a bad pick up in the distributor.I checked the spark last time it did it with the tech right there and he said it had great spark so now I am really stumped,sounds like he is too.They said they checked the fuel system and everything checked out so...I hate this engine,I love working on my 350 and my 22re but this 3.0 is the last one I'll ever buy.Too much $$$ to work on.

rivercat

i feel that

Bumpin' Yota

hmmm I'd find a different dealer...

Any codes?

Doc279

Since the fuel pump is inside the fuel tank and pushing the fuel - the system can not vapor lock. That is why there is a return fuel line to the tank.
When fuel vaporizes in the line due to a heat source - there is an air bubble but it is displaced by the fuel being pushed through by the pump. Check the fuel cap - it could have the vent clogged.

Need to make sure the fuel pump is running - could be a relay as previously stated. Does the engine crank ? I assume it does but does not fire off.

my 1990 3.oL started acting funny here while back. It would not start suddenly after being fine all day - my starter would not turn the engine over though. replaced the wire between the battery and the fuse block and it has been fine since. The 3.0L engine has expensive parts and is not easy to work on ! Runs great when it's right though.

JEDI87

Those guys are idiots!It ended up being a bad pickup in the distributor.They wasted 2 days of my time trying to figure out why it was "vapor locking" and it wasn't even that.It died on them after testing everything and they checked it and it had no spark to the plugs,great spark to the cap.They stuck a distributor from the shop in it and it ran great.They told my wife that they ordered the new distributor and they would put it in.I had her call back to find out how much because I could do the distributor easily,they said just the dist. was 490,Nope,I bought one from the Kragen for 165 with a lifetime warranty.Runs great.I even got a $206 refund from the cold start injector they stuck in because they said that was the problem before,"it's stuck open flooding the engine".I could have done it myself but wanted the labor warranty.

Watts&Volts

There are two other problems you may have in the future that resemble this.
1 the ground on top of the tank corrodes and sometimes even breaks off. The best solution for this is to solder it to the tank and seal it with goop or some other water proof adheasive sealer.
2 The wiring harnes connection under the passenger seat corrodes and causes all kinds of trouble. Example, when I turned my park lights on it turned my fuel pump on!!! Just 2 contacts in the harness that were connecting through the corrosion.

JEDI87

It did it AGAIN!I was in Placerville this time.I replaced the distributor and it seemed to be fixed for 2 days.I went outta town today and it did it again.I was stuck for half an hour till it decided to reset or whatever.It finally started and ran fine,well it chugged for the the first mile or so then it ran fine.I am at my wits end.I don't want to take it back to the dealer because obviously they can't tell their butt from a hole in the ground and I don't want to pay somebody else to get the same "I don't know answer".

JEDI87

Could the afm cause this?How about the fp regulator?I am going to diagnose this som b#$%h myself.

drkgypsy

Check the gas temp sensor in the EGR Valve,<---gas temp sen. only on California vehicles

Check ALL fuel hoses&connections ,

Check fuel pump, fuel filter, pressure regulator....for starters

And fuel pressure is 38psi to 44psi w/ignition switch in the ON positition, if high, replace the regulator. Low check the above listing.

The fuel pressure is 38psi to 44psi at idle, w/ the vacuum line disconnected from the reg and plugged closed.

The fuel pressure is 33psi to 37psi at idle, w/ the vacuum line reconnected to the reg.

The fuel pressure should stay above 21psi for 5 minutes after the engine has been turned off.

JEDI87

Is there a way to test the fuel pressure on the 3.0?I haven't found anything yet.Today after work I am going to change the fuel filter and use a friends afm to see if it still does it.Egr could do it too huh?I keep thinking it has to be a sensor or something because once it chugs and dies I can wait 15-30 minutes and it starts up again,but it chugs for a mile or so.It never dies while driving,just after I have shut it off for 15-30 minutes.No black smoke,no codes.