obxtarheel91

i have a 1995 4 runner with the 3vze 185,000 miles and it starts up just fine, sounds fine no knocking or anything. revs up and sounds fine in park and i have no Check engine lights...

But when i put it in drive it seems to stutter and bog down.. once it does get going it goes away but while driving down the road it seems to be lacking power and has a strong exhaust smell
feels like a miss at idle, kind of a slight shake to it.. its been to the shop 4 times in the past 2 weeks and they tested the fuel pressure, the converter and cleaned out the throttle body
and apparently adjusted my distributor and advanced the timing which i didn't ask him to do. Didnt change a thing.. i could hardly get out into traffic when i picked it up from the shop.
i bought it a few months ago and it ran ok, but shortly after i bought it i got a check engine light for EGR and a lean code 25, got the EGR replaced and the code went away, except the
code 25 it wouldn't go away for about 2 weeks then i replaced the intake hose which had a crack in it and now the code is gone.. but anyways i didn't get the bogging down until after i replaced
the EGR and Fuel filter.. and it really started one night a few days after when i was going down a dirt road and it started out of no where..limped out of the woods and turned it off looked around couldn't
find anything out of place.. started it back up and accelerated fine.. it seems to go away after i restart the truck but comes back within a few minutes.. this is driving me crazy ive spent way
too much money on this thing, i love the truck but im afraid its gonna break down on me eventually and with the mechanic not wanting to mess with it i'm kinda screwed

i have replaced the flowing.. spark plugs, wires, cap & rotor, ECT sensor, TPS, VAFM, Fuel filter, EGR, EGR modulator, PCV, some vacuum hoses, gas cap, Seafoamed everything, and changed oil/filter

obxtarheel91

anyone

dropzone

iTrader: (6)

so you gave it an hour and 53 minutes on a holiday weekend?

someone will chime in

do a compression check, 160-200k is about when these things like to blow head gaskets..not saying this is your issue but might as well eliminate it
what does your coolant look like/

obxtarheel91

sorry i forgot it was Easter

the coolant looks fine and the oil looks good, it dosnt run hot but from what i have read it can crack between the cylinders so its prolly a good idea to just check it, but it seems like something else because when i turn it off and flip the key to the on position to kinda prime the fuel for a sec it will run like a bat outta hell and even spin tires on loose gravel.. all the power is back and runs great for about 10 mins and then it will start to sputter again, im not a mechanic by any means and everything i know about the engine thus far is from reading these forums and i am very very grateful

it all started after they changed my EGR valve and Fuel filter.. maybe they put the wrong filter on? or maybe something else in the fuel system got fouled up in the process.. idk im just connecting the dots like i said im not much of a mechanic and i have no Check engine light to guide me to the real issue , thanks for the reply

obxtarheel91

so if i unplug the TPS i can actually drive it.. but it still has the symptoms, if i press the gas hard to give it wide open throttle it still bogs down, maybe an electrical issue? or maybe since the tps is unplugged its not using as much fuel? man im confused as hell

obxtarheel91

ok, the EGR code has come back again (code 71) and it wont go away ..im not sure why, i have a new EGR valve and i have tried 3 different modulators i grabbed from the junk yard, i'm not sure what the chances are that they were all bad.. that would be some terrible luck...

but anyway, im not sure why it keeps coming back, i've even double checked the VSV's to make sure it was hooked to the correct one.. the mechanic is leaning towards a timing issue like maybe the timing belt needs to be changed, after all i'm not sure when
the last time it was changed before i bought it.

The PO said it was done "not too long ago" . Who knows how long ago that was, The mechanic checked it with the light and said it was "off" and he tried to advance it with the Distributor and couldn't get it to "where it should be"

But before i drop a bunch of money doing that i wanna be sure i've checked everything else, i've read that there are a number of things that can retard the timing?

when i changed the spark plugs last they had some crappy Autolite plugs in there and it had that grey looking tip on all 6 of them.. dont know if that helps but any advice would be greatly appreciated, i love this truck and i just wanna fix whats wrong with it, Thanks

oh and ive tried taking the vacuum hoses off of the EGR and plugged them and tried to drive it and test it out and it was the same, also applied vacuum to it at idle and it wanted to stall so from what ive been told that means the valve is fine

irab88

iTrader: (4)

Try pulling the fuel pump. My strainer had disintegrated and ws clogging the fuel pickup, causing very similar issues.

obxtarheel91

thank you for the response wow that was in bad shape!

yeah i'm leaning in that direction i definitely feel as if its a fuel issue, i need to check the pressure myself and see what its doing under the bogging condition because something tells me the mechanic didn't go that far.. because when i asked him he said his co-worker did it and he "thinks"
they did, and also it wasn't bogging as often when they tested it.. now its every time i put it in gear and go..

and i think the rough idle and the timing issue i'm getting is from the TPS not being installed correctly, it definitely wasn't doing that before with the old Denso one, i did it myself and i don't have much experience.. all i did was mark where the screws were and line it up as best i could..
and along with the shaky idle its shifting too early (just like it was with the TPS unplugged) and also there is no change in idle when i unplug it, i'm gonna go over the proper instructions tomorrow and get it set in there correctly

and with the bogging that is with it plugged in and without, its also doing it going up the bridge down the road from my house now

One thing i did notice is that i can squeeze the fuel line going into the filter and completely stall the engine and im not even squeezing it very hard, is that normal? and also do you think the incorrectly installed TPS would cause an EGR code to come up? like maybe the ECU is reading things wrong?

obxtarheel91

Well here is an update,

I rented a fuel pressure tester from Auto-zone and as you might guess it didn't have the banjo adapter piece.. so i just used the "T" that was in the box and tied into the line coming from the tank and tested the line after the fuel filter
and the one before it, it was pretty much the same so the filter is fine im guessing, but the fuel pressure was sitting at 30 psi at idle and when i unplugged the FPR vacuum it made no difference in the pressure.. also when i
applied a hard throttle it would drop below 25 psi and when i was driving down the road giving wide open throttle it was going as low as 20 psi.. even in park when i was revving it up it was going down to 25 psi

is it safe to say the Fuel pump is the issue? or is there something else in the fuel system making it lose pressure, or am i just going about testing it all wrong? i know the cold start injector is not leaking and neither is the FPR from
what i can tell, i unplugged the vacuum and left it running it was not spitting out fuel or anything, and i looked all around the engine the past few weeks looking for possible leaks and i have found nothing that i can see
another thing is after i hook in the tester to the line and then go to turn the key, it does not prime, it only builds up pressure as i crank the engine, not sure if thats normal
any advice would be appreciated, thanks

obxtarheel91

Solved: it was the fuel pump... it runs great now and has power again


thank you for the suggestion!!