Thehollywood811

I must have forgot to mention I replaced my tps

RJR

Sorry, you mentioned it but I missed it. Print too small for my old eyes...

Thehollywood811

Haha no worries! The only thing common I can think to replace would be the o2 sensor and the fuel pump maybe... but we put a code scanner on and the o2 appeared to work okay and if it was the fuel pump wouldn't it do it at high rpms even more so?

vital22re

iTrader: (2)

Have you checked the timing between cams and crank? Make sure all your timing marks line up. Then recheck the distributer timing.

Terrys87

iTrader: (1)

I am having an issue with Code 11 and after changing out 3 ECU, 5 differnent TPS, 3 AC switchs and 2 harnesses, I finally took it to a mechanic and he used a scanner. I wasnt aware that there is actually a scanner out there. You are really the first person I have seen mention a scanner. I get code 11 with the paper clip and he gets 13 (If I recall right) and he knows the paper clip test real well. He said the scanner came up with "Low Fuel Trim".

I would not think the computer is smart enough in these to see a weak fuel pump and that is what his test are pointing to. Could be a Fuel Regualtor as well. I am installing a new fuel pump and regulator tomorrow and am being optimistic and pessimistic on this repair.

I have done the FSM, 4Crawler, and numerous other Toyota sites looking for information on the TPS issue and maybe it is possible that the fuel pump is an issue for the TPS. Not trying to hijack your thread but the mechanic I went to and another I talked to says the scanners are really good and I am hoping that some how the fuel pump is an issue with the TPS. I personally dont see the computer being smart enough to see things like that but time will tell.

Thehollywood811

Wow really good to know!! And my friends dad is a mechanic and has a thousand dollar scanner... it tells everything! Unfortunately he us very VERY busy and doesn't use it much so it's hard to get a hold of him when he has time to use it... but any way let us know how that turns out I'm curious just don't have a lot of $$$$ to go by a fuel pump and regulator at the moment

Kalihi,HI

Aloha from Hawaii, I've been dealing with a similar issue on my 3vze 94 pickup M/T, 4x4. I noticed a drop in power at higher speeds 35+mph where my RPMS would continue to increase, but my speed wouldn't. My fan pulley bracket then froze up, causing one of my belts to bust, so of course new fan pulley bracket and belt. I then changed my timing belt, water pump (was leaking), thermostat, PCV, VAFM (out of spec) and upper air duct/hose which had a huge crack in it, O2 sensor (out of spec), TPS (out of spec) and correctly adjusted it, replaced all 6 injectors with reman'ed Densos, new plenum gasket, throttle body gasket, cleaned out throttle body and plenum, new valve cover gaskets, replaced fuel pressure regulator cus fuel pressure was too high at 48-50 PSI and supposed to be 38-44PSI, replaced fuel filter. Truck runs better, but still loss of power, especially under load and going up hills, so bad I can't safely drive it, I had to coast back down a small hill that I couldn't make it up and truck almost died, so that I could get a running start going up it. Fuel pressure at delivery rail is now good at 38-40 PSI when key is turned to On and when truck is idling...However when the truck turned off, the fuel pressure drops to 0 in seconds, when the FSM says it should remain above 21 PSI for at least 5 minutes after turning off engine...I then switched my Headlight relay and EFI relay just for fun and tried starting, it started and idled fine, but check engine light came on with code 25: Air-Fuel ratio, lean malfunction (check engine light was not on before switching relays). Should my fuel pump be my next target? Are there any other tests before going in to change fuel pump? Does the drop in pressure mean I have a weak fuel pump or a leak in fuel system? I can't find any leaks. Any help is greatly appreciated..my trucks been out of duty for 2 months now. Mahalo!

RJR

Hold on! If rpm's are increasing but speed is not with a manual transmission, your clutch is slipping. There's really no other conceivable explanation. I'd be looking at the clutch adjustment, age, etc.

Thehollywood811

I wish It was that easy, the signs do appear like clutch slippage but my truck Boggs down and backfires and stuff like that. If a clutch slips you would hear the rpms go up when it slips due to the fact that the load is decreased on the engine

Thehollywood811

Forgot to mention that my idle screw located on the throttle body is almost bottomed all the way out just to get the idle to about 700 rpms.. not sure if that makes sense or not and also my afm is about 4 clicks lean to compensate for my flamethrower injectors

Kalihi,HI

Anybody got any ideas about my fuel pressure (tested at the LH delivery pipe as FSM says) being 38-40psi with truck on at idle (FSM range: 38-44psi)but then dropping to 0psi within seconds of turning off truck. FSM says the pressure should main above 21psi for at least 5 minutes after turning off truck. I have changed fuel filter, new reman'ed Denso injectors, new pressure regulator, all new crush washers, fuel pulsation damper seems fine, and no apparent fuel leaks. I'm thinking I need to drop my fuel tank (or remove my bed??) and replace my fuel pump?? Any help is greatly appreciated!

Thehollywood811

I've heard cold start injectors can stick open. Maybe unplug it and see what happens?

nv4runner

There is a check valve in the fuel pump that is supposed to keep that 21psi after you shut it off.

So when you really get on the gas pedal the RPMs go up but the speed doesn't? If so that is a worn out clutch my friend.

Thehollywood811

My truck Boggs down and backfires and almost dies when I get on it

Terrys87

iTrader: (1)

I swapped in a new fuel pump and it didnt fix my problem. I was hoping that maybe it would, but didnt see how it really could cause an issue. I had a friend over that has a lot more experience with these then I do and it has him stumped as well. I need to get the bed back down and see if that one mechanic with the scanner has any other suggestions.

Thehollywood811

Have you tried a new pressure regulator yet?

Kalihi,HI

Ok, so the fact that my fuel pressure drops immediately after turning off the truck means that the check valve is malfunctioning/broken and I should check and/or replace my fuel pump? Is it easier to drop the fuel tank or remove the bed?
And I believe these are separate issues because the increase in RPMs with no increase in speed (at 30+mph) was happening before the current issue of not even being able to get up a small hill, where I am gassing it, but there is no increase in RPMs or speed.

thesculptor

I'm having a problem with my 89 Toyota PU starting. The mechanice mentions the circuit opening relay. He said the one under the hood was ok. What do you mean by the (Could some thing be causing the Circuit opening relay to drop out ??) and what could cause that? Thanks

Terrys87

iTrader: (1)

That is todays project to swap that out and see what happens. Got my fingers crossed but the optimism isnt there. Still hoping.

Terrys87

iTrader: (1)

I really suggest loosenig the bolts on the drivers side way loose and remove the bed bolts on the passenger side. Depending on rust and such that can be no small task. Some bolts can be tough to get loose and out. In some occasions I even have had to cut the bolts.

Dropping the tank, the hoses dont have much slack in them and depending on the condition of your high pressure fuel line on the fuel pump bracket or you break it, due to the hose getting to tight and bending then causing it to break, that is an expensive and hard part to find.

Lift the bed, I think you will be so glad you did later on.