2.7 wont stay running

Unmetered air (vacuum leaks) will cause problems.
The fuel pressure regulator is fully open at WOT which would be low vacuum. X2 on MAF problem. Check for rips and tears in the intake between MAF and TB as well.

 

Hey, new to this site. Did any one ever find out what was causing this issue? I have a 95 Tacoma 2.7L with the same issue. When I first start it, it runs for about 5 seconds and dies. If I hold the gas peddle down to about 2krpm's for 30 sec or so it stays running fine. I just got done installing a new engine and changed the crank positioning sensor. Any help would be appreciated

 

It only runs with the pedal down? Check your fuel pressure, for one. You'll have to check that all the other sensors and connections are done properly as well.

 

No, after the initial 30 sec or so it runs fine after that. its anytime I have to start the truck.

 

Doesn't that have a distributor? Check for pitting on the cap and rotor, if so, replace. Definetly check the fuel pressure. If there is none at startup, then builds quickly, the check ball in the fuel sender is shot. Replace the fuel sending unit and the filter. There should be pressure on the fuel rail at all times. The check ball keeps it primed and pressurized.

 

Could be the fuel, the truck was sitting for about a year. Will update the post once I check the fuel pressure. I suppose the sending unit is in the fuel tank right?

 

Yep. I think the filter is on the frame rail. It's in the tank on the 2gens.

If it sat for a year, things may just be gummed up. Get the old stuff out and/or fill up with new fuel, injector cleaner, and gas dryer. Gas turns to varnish over time and clogs stuff up. Ethanol absorbs water and the water separates when it sits. Condensation inside the tank also causes problems over time.

You may just have a fuel quality problem.

 

I unplugged the Throttle Position Sensor and it now starts fine, What do you think? I guess I might need a new one? Also I used Sea Foam in the tank and throttle, which didn't seem to make much of a difference.

 

Meter the throttle position sensor. It should have a smooth resistance reading through it's movement.
Looks like you found the culprit.
This is why I always advocate for checking pressures and sensor readings. Easter egg parts replacers would have had you wasting money.

 

Glad to hear that replacing the throttle sensor will fix this problem. How would I check the resistance with it plugged in? The darn thing costs something like $100. But oh well I guess if it's going to fix it, it will be worth it.

 

i have the same problem with my 2.4. except mine will idle. i tore my exaust out and burned out the cat. that might be the idle problem if they get plugged they wont run worth shit. but i completly tore my motor apart and replaced m head gasket and mine still doesnt run right either and everything is hooked up.
i also changed the plugs.

 

I looked up how to check the Throttle Postions sensor pins 1-4, 2-4. I changed the sensor and also had to change the EGR tube it had a leak at the exhaust mani. Now its runs great. Still have a check engine light "Crankshaft error" which I'm not sure why, I had originaly changed that one. It might be the timing that might be off.

 

thmpsntrv91, If you have a distributor in your truck try turning the teeth on it one tooth counter or clock wise from TDC to see if your timing is off. Had the same issue on my 4Runner.

 

Im having the same problem with a 1995 tacoma 2.7 engine. I bought it and the previous owner changed the head gasket. I havent been able to figure out what is going on with it. How do you check to make sure that the distributor is corrently in place?

 

Pull the distributor, on the end is the gear it has a mark on one of the teeth and a mark on the distributor body line them up, then put back in place. I have the service manual in as pdf file, if you want it let me know.

 

Thank you very much for your help. I will do that this weekend and will download the manual instructions. I'll keep you updated and hopefully this will get it going.

 

Please provide me the PDF file for the Tacoma service manual.

Thank you.