Jump to content

Fuel Pump Changed/ Where Is Fuel Filter?


mini-wini-dan

Recommended Posts

I just stalled near Harper Oregon on us 20. Towed to Toyota dealer where they diagnosed fuel pump failure. Was replaced and now running but must crank starter longer and pump accelerator several times to get vehicle running. Just wondering why? Before the change this vehicle would start immediately without even touching accelerator. Just wondering is something done during change over caused restriction in the line. Maybe need to replace fuel filre?

Link to comment
Share on other sites

It is under the rear of the intake manifold. It is not exactly easy to replace and no doubt needs it most likely it's the one that came with the MH. It can be done with out removing any thing other than the filter you'll need a 12 MM and a 17MM wrench/socket Make sure you do not drop any of the copper rings when putting it all back togther. If the dealer replaced the pump and not the filter they should be ashamed of them self's.

Link to comment
Share on other sites

I just stalled near Harper Oregon on us 20. Towed to Toyota dealer where they diagnosed fuel pump failure. Was replaced and now running but must crank starter longer and pump accelerator several times to get vehicle running. Just wondering why? Before the change this vehicle would start immediately without even touching accelerator. Just wondering is something done during change over caused restriction in the line. Maybe need to replace fuel filre?

It takes very little gas to start the engine and a heck of a lot more to make it go down the road. If the fuel filter was restricted, your rig would be spitting and chugging while climbing hills. I don't know what is wrong with your rig, but if it drives down the road OK, I doubt your fuel filter is the problem. I'm not sure either why pumping the pedal makes a difference with a fuel-injected rig. If it had a carburetor it would make more sense (to me) since then, pumping activates the accelerator pump and squirts raw gas into the engine. No such action with EFI. Holding the pedal most of the way down however, when cranking the engine sends more gas into the engine. Kind of the opposite of a carbed vehicle since with a carb - holding the pedal down is the way to "unflood" a flooded engine.

My 1988 with a 2.4 and EFI sometimes when warm . . won't try to start until I stop cranking, turn the key off and sort of "reboot." Then, on the 2nd try, it always takes right off. Obvisously some valve or sensor gets reset. I never explored it further since it always starts after I turn the key "off", then back "on" and crank again. Back to your rig - as far as I know - pumping the pedal should pretty much accomplish nothing on the EFI setup. If you are 100% sure it IS what is helping it start - seems that offfers a clue as to how to diagnose since something is not acting as it should.

What exactly happened before that ended up in someone "diagnosing" your need for a new fuel pump? I'm also wondering what sort of shop would do this, and NOT install a new fuel-pump pickup screen and a new in-line filter by the engine cylinder-head at the same time?

Link to comment
Share on other sites

The job was done by a toyota dealer in boise idaho. They showed me an under-sized pump that had been installed by the previous owner. This pump was not made for the system and the wiring was modified to adapt it. The dealer went back to the pump designed for the vehicle and attempted to re-wire it as directed for the toyota pump. I just drove the vehicle 300 miles and it was running better than ever 15.5 mpg and handled elevation with hills in southern idaho and northern utah. It started easily after gassing up once. Later after parking it in a rv park it went back to churning a lot and finally starting. This vehicle used to start up on the first crank and that seems to have changed after the change-over. Thanks for you input.

When you start yours do you depress accelerator or just wait for the pump to bring it in? Also, I hardly touch the pedal on my 2.7 tacoma as well and it is carburated. and starts up immediately.

Link to comment
Share on other sites

2.7 Tacoma engines are FI. You should not have to touch the gas just crank the engine "pumping" a FI engine really does not do much. Most early FI cars had a full throttle "clear flood" on crank" that shut down the injectors. The filters are good size not only do they clog with junk they collect water.Fuel pressure is very important in any FI engine a few # of fuel pressure loss has a pretty good effect on overall performance and can cause fuel pump problems. The pump brings the pressure up with in a second or two it pumps far more fuel than the engine uses and returns a good portion to the tank. Bottom line there is no delay from when you turn the key on till it starts as far as pressure is concerned. The filter IMHO more than likely has never been replaced it not only is well hidden it's also a pain to replace .Before I went about replacing parts I would change the filter I have a $5 bill that says it hasn't been unless the dealer was doing their job.There are other things that could cause your problem but they usually don't change over night. A filter is pretty cheap and more than likely needs to be replaced any way it is part of normal maintenance for good reason.

Link to comment
Share on other sites

When I start any FI engine, I turn the key on and listen to the fuel pump, when the pump quits running, the fuel system is at full pressure and it should start more or less instantly. If the engine is properly tuned, I never have to touch the gas pedal to get it to start. Before I did the valve adjustment on my Toyhouse, it would run rough for a couple of minutes at start up. After adjusting the valves, it runs smoothly right away.

Link to comment
Share on other sites

When I start any FI engine, I turn the key on and listen to the fuel pump, when the pump quits running, the fuel system is at full pressure and it should start more or less instantly.

I don't think hearing the pump shut off has anything to do with it achieving full pressure. It is on a timer. It shuts off regardless if there is pressure or not, once the key has been on and the engine has not started. As I recall, the mid-80s EFI system in Toyotas that fires a half-charge of fuel every engine revolution, has an electric fuel pump that runs all the time and pressure and the 30-40 PSI pressure is maintained by a spring-loaded relief valve.

Link to comment
Share on other sites

One added note. The EFI system in the mid-80s Toyota stays pressurized after you turn the engine off. Obvisously not forever but . . if the injectors don't leak off, and you go to restart after an hour of sitting - the fuel lines to the injectors are already pressurized even before the fuel pump gets any electricity. Toyota gives a "5 minute" leak-off test, i.e. the system is supposed to hold 30 PSI for at least 5 minutes after shut-down. Regardless - the fuel lines are full and waiting - and once the electric fuel pump gets power - pressure comes up almost instantly (unless there is problem somewhere). I suspect on my 1988 2.4 EFI, the injectors are worn a bit and leak when the engine gets turned off. I say that because if the engine is hot, and I shut it off, and then go to restart maybe 15 minutes later - it acts as though it's a little flooded. No big deal since it clears right up.

Back to the poster's problem - I still cannot see how a clogged fuel filter can cause a starting issue and NOT cause a driving issue. That makes zero sense to me. Takes nearly NO fuel flow to start the engine and MUCH more flow to run pulling a load. A dirty fuel filter equals restricted flow.

Also - I believe it takes very little fuel pressure to allow the Toyota to run. Even at 20 PSI. Nowhere near as critical as some newer systems that must have 60 PSI and won't run at all at 50 PSI (like the GM C.P.I. system used in mid-90s Vortecs).

Link to comment
Share on other sites

On the specific subject of the engine reacting, one way or the other, by pumping the pedal. That leads me to suspect you've got problems with the throttle position sensor. If suspect, I'd check it out with a feeler-gauge and an ohm-meter . . or just put in an new one for $60. It is what moves back forth when you move the gas pedal and if working correctly - sends a signal to the ECM for more or less fuel.

Link to comment
Share on other sites

OK we just traveled to Ogden Utah without incident yesterday. Left the campground this AM and traveled about 50 miles east towards Cheyenne Wyoming. Stopped at a rest stop to shoot a photo while I left the vehicle running. When I got back to drive it had stalled and would not start again. Tried cranking numerous times and finally called AAA for a tow to Toyota dealer again. Just out of curiousity after making the towing arrangement I attempted to start it again and it started. So I called to cancel towing and proceeded 20 miles when it sputtered and stalled again. Again many attempts and would not start. So arranged the towing again and got towed back to Ogden for another round with the toyota dealer. And now again after getting dropped off there it started right up easily and immediately without much cranking. About 1/2 later tried again and would not start.

This is beyond frustration. When driving down the road it has been running beautifully good gas mileage 15-16 mpg has good power. I am beginning to wonder if watered down gas could do this? I will probably have them drain the tank tomorrow and put high test in and let them test the pressure from the new fuel pump. Any educated people who can share info concerning this may be helpful here. I have a lot of miles ahead of me going back to PA.

I have put about 24000 miles on this vehicle with minimal problems and am quite perplexed about who to turn to and how to proceed at this point. If this continues I May even consider selling the vehicle out here if I can find a contact person to store it for me. The vehicle has 97,000 miles on it presently.

Link to comment
Share on other sites

I am beginning to wonder if watered down gas could do this? I will probably have them drain the tank tomorrow and put high test in and let them test the pressure from the new fuel pump. Any educated people who can share info concerning this may be helpful here. I have a lot of miles ahead of me going back to PA.

Seems you need someone to do some diagnostic checks and approach this in a logical way. Adding high-test makes no sense, nor does suspecting water in the fuel, fuel pressure, etc. At least not to me. There is no water-trap in the vertically mounted fuel filter. First of all - when it is NOT running - do you know 100% for sure it is a lack of fuel problem and not a lack of spark? If it was mine - when in the mode of not starting - I'd immediately check for spark and verify if it there is or not. If you are then SURE it is not a spark issue - I'd use the Occam's Razor approach and look for the simpliest and most obvious fix. To me - that would be electrical components that also wear from constant mechanical movement. That includes the throttle position sensor (moves whenever the gas pedal moves) - and the air-flow meter. Both can send an erroneous signal to the ECM and stop all gas flow to the injectors. Both can be checked with a simple ohm-meter and need not be replaced on a "guess." You said earlier the fuel pump was replaced because it was insuffient in flow or pressure? How so? It takes very little pressure to make the engine run. But of course - you have to verify the pump IS working. There is a logical sequence of checks to make and all are outlined in the Toyota service manual section on fuel injection. None require any special tools. At this point - any attempted fix with no logic involved is kind of like pissing in the wind and hoping to stay dry. And note - I'm not trying to be a wise-behind. I've worked as a mechanic for a long time and know how frustrating intermittent problems can be. Even more reason to use the logcial, step-by-step diagnostic approach instead of just replacing things.

Link to comment
Share on other sites

One added thought. Are you sure your "check engine light" works? Pretty much all the possible problems I mentioned should of made the "check engine light" come on and then be stored in the computer memory. If you are confident the light works (no burned out bulb or something) - then the field of problems gets a bit narrower. A bad throttle position sensor or air-flow meter should throw an error code. Same with no spark. Even if the computer itself crapped out - there is a back-up system to keep it running. A non-working fuel pump or a lack of fuel pressure however will NOT register an error code. No sensors for that except I think for the fuel-pump relay not getting the proper signal to run. That WILL throw an error code but a relay that simply craps out will not. Neither will a faulty pump, plugged filter, bad fuel-pressure regulator, etc.

Link to comment
Share on other sites

The 2.4 has no TPS it's controlled by the AF sensor. With out a fuel pressure check all bets are off. It needs to be about 35 PSI to preform properly. First thing first the fuel pressure is constant that is the bench mark every thing else is variable, temp, air flow, timing etc.The system is time based against a fixed fuel pressure the electronics control the amount of time the injectors stay open to maintained the systolic mix.They are many things that can cause your problem a leaking cold start injector could cause a hard hot start for example, from here it's nothing more than a guess but before I would go any further I would check fuel pressure and proceed from there. You can jumper the diagnostic terminals and see what comes up if it does nothing then you'll have to find out why the light does not work. The system is pretty crude and will only give you some pretty broad guesses as to what's wrong.

Link to comment
Share on other sites

The 2.4 has no TPS it's controlled by the AF sensor. .

That is ABSURD! The engine would not run without a TPS. Toyota part # 8945228030. Toyota used the same TPS (throttle position sensor) on the 2.4 22RE as well as the 2000, 2500, and 3000 cc engines from 1984-1989 on trucks, Camrys, Supras, etc. I think every fuel injected gas engine on the planet that is not "drive by wire" has a TPS. So do many diesels to run the electronic transmissions. Some also use throttle position switches (not sensors) to run emission controls.

TPS is a major wear item since it moves whenever the gas pedal moves. I've had to put three in my Ford diesel truck in the past 240,000 miles. Already put one in my 1988 22RE. It is just a variable resistor not much different then the volume control on a radio (with a rotary knob). If it gets worn, or gets dead spots in it -it senses false signals to the computer about where the gas pedal happens to be.

Here a few photos of the TPS on my 1987 22RE engine out of a dually box truck. My 1988 Minicruiser has the exact same unit mounted to the throttle shaft.

Also attached a few photos of the fuel filter since the poster asked (unbolted from the mount bracket).

post-6578-0-91328700-1438786090_thumb.jp

post-6578-0-32531800-1438786092_thumb.jp

post-6578-0-97718700-1438786093_thumb.jp

post-6578-0-99826600-1438786095_thumb.jp

post-6578-0-77560100-1438786097_thumb.jp

post-6578-0-90205100-1438786098_thumb.jp

post-6578-0-55753400-1438786100_thumb.jp

post-6578-0-11607800-1438786102_thumb.jp

Link to comment
Share on other sites

All is well except for my pocket book. The Winnie is running great again once a genuine toyota fuel pump got installed. The first dealer in Boise charged $1300 to diagnose and install an after market pump which failed 350 miles down the road from them. I was towed back to Ogden Utah where they replaced the after market pump that failed on 1 80 east by Echo Canyon. So that one took but I am disputing the charges since the first attempt did not work and left me stranded again. Their charge was around $800 and change but at least it is running great again. I will be glad to pay for the services rendered but I think there needs to be some adjustments.

I'll keep you posted on how the Toyota Corp will help if at all.

Link to comment
Share on other sites

Nice that it is fixed. I put an aftermarket pump in my 1988 that cost me $27. That was 8000 miles ago and it's been fine. Not all aftermarket pumps are bad.

Link to comment
Share on other sites

I did change a fuel pump once on my 67 chevelle 283 engine. Was easier than dropping the gas tank to access it. It hurts to pay big bucks for something like this and then twice is too much!!

Link to comment
Share on other sites

I did change a fuel pump once on my 67 Chevelle 283 engine. Was easier than dropping the gas tank to access it. It hurts to pay big bucks for something like this and then twice is too much!!

I had a 64 SS Chevelle with a 283 for a long, long , time. Changing that mechanical pump on the engine had its own problems. That damn pushrod shaft that drives the pump can be very difficult to lift back up and keep it out of the way when changing pumps. There's a drilled hole in front the SB engine somewhere that you can stick a jam-bolt into to hold that pushrod out of way. Great car - back when I had some respect for Chevy and GM.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...