Low RPM rough Idle with bad acceleration

Hey all!

I am trying to figure out my issue with my 95 3.0 4runner. It starts fine then it rough idles at a low RPM and it has terrible and rough acceleration. I changed the MAF, distributor, plugs are good. Fuel pressure test is good so its getting fuel. It runs like it is not getting enough gas. Fuel filter changed as well. Gunna put in a new TPS as well since I have one, but any other thoughts on what it could be?

Thanks in advance all!

 

Definitely following to see if anyone has advice for you. I just bought a 1991 and the issue you're describing sounds like mine. The first thing I'm doing is fixing any electrical problems because it has a ton of aftermarket electronics causing a TON of parasitic drain. I'm hoping there's a bad ground. But I'm going to be looking at the intake into the throttle body as well. Maybe it's a vacuum leak?

 

Yea electrical is something I am worried about as well. I hope you get some answers! I took the throttle body off and gave her a good cleaning too. Forgot to list that in my initial post. Could be a vacuum leak. I actually dropped it off at my mechanic today (when i fail hahah) so he is testing that.

Ill keep ya updated.

 

Update my mechanic is stumped so far haha. He is going to take a look at electrical. He rechecked plugs, checked new distributor install, checked the TPS, Made sure the MAF was good etc.. Hoping to hear more soon. hope she is not a goner because there is only 136k on it!

 

So we got it idling well but now we get a code for the MAF but I put a new one in mid feb! Any thoughts would be appreciated. We put in a new ICM which helped with the idling but now acceleration sucks and MAF code. Maybe a faulty new MAF?

 

One thing that's easy to overlook is a leak in the intake tubing. My brother had a Corolla back in the 90's that was running like shit due to a cracked or tear in the tubing throwing off the MAF sensor.

 

Second on the MAF sensor & related connecting tubing, also look inside to ensure nothing is blocking the flow, Have seen leaves be wrapped up around the element and it caused all sorts of drive ability issues.

 

Thanks for the input! Ill take a look!

 

Question: For you rig what kind of engine air filter are you running? I ask because I learned about an engine code being thrown out pointing towards a MAF sensor but in reality it was simply because someone was running a K&N filter that was too heavily oiled thus restricting intake airflow. If you're running a paper air filter what condition is it in? Also check the airbox intake tube for anything that can be blocking airflow all the way down into the wheel well area. 0.02....

 

Thanks for

Thanks for the tips! I am just using your standard STP paper style filter nothing fancy. Filter is clean, but I am going to check the intake a little closer. I did not check in the wheel well area!