RylerTust

I have a 1990 4runna
22re efi
4x4
A/c
P/s
5speed

Wether hot or cold it has a strange stumble in the lower RPM's. starts fine. Runs fine. Idles smooth. But say I'm goin uphill or even on flat when I get to 2-3rd gear, has a strange stumble. Never bad enough to die, but does sometimes slow me down and REALLY piss me off. No vacuum leaks I can tell. Plugs and wires and cap are fine. Clean points. Timing is fine. Just has a stumble while accelerating. And it's a tiny bit better if I go to WOT. Only in lower rpm, 1500-2500, much worse when a/c is on. Any ideas? I was told to replace my fuel filter. Thanks guys.

Tyler

RylerTust

Also, intermittent. Randomly happens. Isn't always there, but more often then not.

kornhuskerwizard

check your tps adjustment

RylerTust

How do I check?

RylerTust

Also! I have a a/f ratio gauge and when this happens it stays in the same range. No rich or lean spikes.

Huntingtruckcletus

im having a similar problem with my 22re. I changed the spark plugs and it got better for about 15 miles then it changed from low rpms to high rpms.. It stumbles at anything over 2400 rpms and wont get over 3000. Have you had your problem move in rpms or is it only at low rpms?

RylerTust

Honestly it went to where it would barely run. Changed the plugs, wires, and MAF sensor and fixed it. Check your tps. Jump the connector like you're checking your timing. I've been told if you do this and the idle DOES NOT CHANGE, the tps is bad. Back up this idea by checking the sensor with a volt meter. Check your fuel pressure at the rail and make sure you're getting enough gas. If it stumbles at high rpm it may be starving for gas. Any check engine light? Try and check those. Even If its not on there still may be something wrong. You may have fixed the problem and then a new one occurred those 15 miles later. Even low coolant messed with my trucks performance and made my RPM's become erratic. Also do the regular vacuum leak check and exhaust leak. I had an exhaust leak on my xj one time and made the truck run like ass in higher RPM's. hope some of these ideas help.

RylerTust

Make sure the plugs are gapped right. That can cause stumble at high rpm. I think it's .030 is the gap.

Huntingtruckcletus

I found my problem I have a gas line going from the intake to the fuel filter that had gone bad. Check this hose it has a plastic cover on it I had to cut off to see that my hose was flattening out and not allowing proper fuel flow!

RylerTust

Glad you figured it out man!

Huntingtruckcletus

Thanks! I had quit searching an was aggravated on the ground just laying under the truck looking at it from the bott side when I noticed the cover on the gas line.. Idk what it was but something just told me to cut the cover off.. I'm betting other people have problems under those covers too.. They just can't see it!