2.7 4 Banger Hesitation

Truck was off the Road for a While. Been Running Good after new Fuel Pump. After about 5k miles. Seems to happen more when its been driven for longer periods of time than Short little runs. I am Having a Lot Of Hesitation Issues. Replaced Plugs and Wires, and Fuel Pump. Run Some Fuel Injector Cleaner through as well. Fuel Filter was Next on my List. Any other Ideas or directions I should look at. Throttle position sensor?

 

what brand fuel pump?

 

OEM Toyota.

 

Fuel Filter is 1 Job that just does Not look easy at all.

 

On my 97 4cyl I was having issues with it cutting out pretty bad to the point I thought it was going to die while driving, I replaced the throttle position sensor and It fixed it.

I noticed the cutting out/loss of power around 50-65 mph.

 

I am Noticing after sittting in Rush Hour traffic it starts Acting up once traffic starts moving again. Hesitation gets Bad.

 

If you do the TPS sensor I believe it was a bitch getting out and I ended up breaking It while pulling it out but the new one went in easily.

2 Phillips head screws hold it in place.

 

Sreppep Just did mine and the bottom screw sucked. Bad thing is it tries to run wide open on start up. How do you reset that?

 

Could you explain in more detail of how the truck hesitates when you drive it? For example like when you press the pedal down does it not feel like theres much acceleration overall at all rpms, or does it not have much acceleration until after a moment with pedal down then it kicks in. Also when was the last time your fuel filter was change and the mileage of your truck? More detail of the issue the better.

Hard to diagnose the issue atm with the info given, but going by what you have said I kind of doubt it would be the fuel filter (at least not just the fuel filter alone).

 

Its Kind of Crazy. 166k And Fuel Filter has Never been Changed. When I Am around town driving or I’m driving on the freeway at freeway speeds it seems fine. Its When I have been in Stop and Go for a Good Half hour or so and traffic starts Moving freely is when the problems seem to start. As I Press the Gas it seems to get to a Certain point and the RPMs Start jumping and truck Starts hesitating and Bucking. At that point it hesitates on the Freeway and Side Streets as well. My Gas Gauge also dropped to almost empty and it went back up again. I get home and let it Chill for a while and its Fine again.

 

Hmm, darn I see it seems more serious then I was imagining. It certainly lines up with a number of possible issues which include both the TPS and Fuel Filter and doesn't perfectly fit just one of them and the symptoms blend together.

For disclosure I really am not to experienced with the TPS system, so take my advice with a grain of salt haha. But, what tips me off though is the fuel gauge jumping around makes me lean toward the fuel filter as the TPS alone shouldn't cause the fuel gauge to act up unlike the fuel filter which does do so (Please correct me if anyone else thinks/knows differently).

Last thing I would want to do is to get you tossing money out for new parts willy nilly, so here is some advice to see if may be a clogged/dirty fuel filter. Haha this is just what I did to diagnose and isn't exactly the professional thing to do.

What I did was loosen the left side of the fuel filter (left being the side of the fuel filter facing the front of the truck). You'll need two open wrenches to do so. When you loosen that side of the filter gas will come out of the fuel line that has already went through the filter itself - catch that fluid in a cup or a pan as best you can. If it is dirty, brown,or filled with foreign material then its a sure sign you have a dirty fuel filter. If the fuel comes out looking relatively clean then its not the fuel filter (at least) and you can tighten the nuts back up and diagnose elsewhere further. -- when you do run the engine again you'll have to hold the key on ignition to get lines filled with fuel again. Haha this is how I found my 136k Tacoma needed a new filter. Honestly not as difficult as it may seem changing it out with the right tools and right approach (I recommend going through the top of the engine in between the intake pipes for the left of the filter, and the wheel well for the right side). Be careful though as the fuel starts coming out of the line almost the instant the bolts are loosened. - Also do this on a cold engine.

 

Any Help is appreciated for sure.

 

Took a Different Route today other than Freeway Bumper To Bumper. Took side streets. Normal City driving and Not Sitting at Idle for 30+ Minutes to an Hour. No Hesitation Issues at all. Very Strange

 

Is your engine coil over plugs or distributor?

 

Distributor. Plugs and Wires replaced with OEM Wires and OEM Denso Plugs properly Gapped.

 

Have you cleaned the MAF sensor lately. You could start getting misfires from that without getting any codes before it gets worse and does eventually throw one. If you do clean it make sure you do a reset on the ECU and let it adjust again.

 

Yes Sorry Cleaned MAF sensor also.

 

New TPS will be here Monday. OEM Part. Any Tricks to that install.

 

Unplug, unscrew and remove. Reverse for install.

 

Not saying the distributor is your issue. But it was mine. My symptoms were somewhat similar to yours. May be worth a read:

https://www.tacomaworld.com/threads/2-7-stumbles-and-bucks-under-load-solved.449971/