Marge

Hi everyone. I recently purchased a 1991 Toyota pickup with the 3vz-e engine and 150,000 miles. I have searched on the forum for power loss with this engine and so far all the posts seem to detail relatively drastic power loss. I am only experiencing fairly minor power loss. The power loss occurs intermittently and always seems to happen when accelerating in 2nd, 3rd, or 4th gear. I will be accelerating from a stop and once I hit second the truck seems to accelerate very slowly even though I depress the accelerator more and more. Another thing that could be connected is that sometimes when I am cruising with the accelerator barely depressed the truck will buck once as though the engine is not getting enough fuel. Perhaps the injectors are clogged?
Any information will help.
Thanks a ton,
Marge

rentedmule

You may want to run some injector cleaner through it, but if you're noticing that much power loss something out of a bottle probably won't help much. I really like the Lucas upper cylinder lubricant / injector cleaner, it quiets the engine down alot too. Changing your fuel filter is probably a cheap place to start as well. If it's clogged it could starve the engine when you accelerate. I'm pretty sure there are write ups in the tech section for the latter if you're a do-it-yourselfer. Good luck!

Marge

I changed the fuel filter and did the seafoam treatment when I first bought the truck and it seemed to be great. Then this problem started happening about a week after. Another forum member said perhaps my fuel pump was starting to fail.

Where to get that Lucas upper cylinder lube you are talking about? And once I get it how to apply it to the engine?

Thanks a ton for the info,
Marge

rentedmule

I'm not sure where the Lucas products are available in the USA. Most parts stores in Canada carry them. There is probably a similar product made by another manufacturer. You just add it to your gas like most other injector cleaners. I found it was one of the only treatments like that that really made a difference. Engine was noticibly quieter and smoother after a few short drives even though I regularly used other injector cleaners. Don't have any input on the fuel pump, sorry!
cheers!

Snorkeldepth

I saw the Lucas products at Autozone recently.

Marge

Thanks guys! I will give it a try.
Later,
Marge

Radyota

Check to see that the EGR valve is working properly, and that all the air intake hose connections are secure. Make sure air filter is clean, and check ignition timing. Check the spark plugs for gap and that they didn't get fouled up by the Seafoam treatment.

Marge

Good call on the ignition timing. I should definitely check that. I just replaced the air filter and checked all the air intake hoses so that part should be good. I never thought about the spark plugs getting fouled after the seafoam treatment...but I suppose that the crud has to collect somewhere. I am not sure how to test the EGR valve but I am sure I can find it somewhere on the site.
Thanks for the info,
Marge

Epic Ed

I'd lean toward a fuel supply issue -- fuel filter or injectors would be my first candidates, though the possibilities others have mentioned are valid, too. I've had similar issues and my solution was to replace the fuel injectors. When he pulled the heads to investigate one injector was cracked and another was clogged beyond hope -- so running cleaner through the system had very little effect on solving the problem.

Ed

Marge

I was kind of wondering if it was the injectors. Sometimes when the engine will dog like that I will get angry and punch the accelerator at the next start and then it will be fine for a while. It is almost as if crap is getting blown out of the injectors and then they are fine for a while. I know that is something else to check but it is more involved than the other things. I will do the EGR and timing check and spark plugs first and then if that doesn't fix it I will move on to the injectors which seem like they will be a major hassle. Thanks for the response.
Marge

motoracer47

how did you seafoam it? seems some do this different ways. when i do it, i use 3 cans. 1.5 for the fuel tank, .5 for the oil system, then 1 sucked directly into the engine through a manifold vacuum tube. how did you do yours? did you do the seafoam before or after you changed the fuel filter?

celica

did you change your plugs after the seafoam treatment - it usually fouls them pretty bad

Marge

For the seafoam I only used 2 cans. About 1/2 can sucked up throught the pcv, 1/2 in the gas tank and 1 can sprayed into the throttle body. I changed the fuel filter after the seafoam. But I think I definitely need to change the spark plugs again. It was the first time I had done the seafoam treatment and I think my plugs got fouled by it.
Thanks guys,
Marge