Any help diagnosing this problem would be GREATLY appreciated. Just got a 4runner SR5 4X4. My problem is that the engine hesitates around 2K RPM, especially noticeable in 2nd and 3rd gear but it runs fine at highway speeds. I'm at 200K miles and It has new plugs, I just replaced the plug wires, dist cap and rotor. It idles fine, only rough when in gear. Any ideas?

 

what engine, year??

 

sorry, 1995

 

have you ever tried seafoaming it? Seafoam is an engine cleaner. a lot of people say great things about it. i tried it myself, notice a little less hesitation with my truck. Search Seafoam on this forum you'll find out more

 

My guess is that it's electrical, possibly a throttle position sensor (TPS), but what the hell do I know? :-)

Just to add what hittman says (because I've actually driven the truck) is that when you're in neutral the engine runs fine at all RPMs. We only experince the hesitation when in gear (between 1500 and 2500 RPM).

Anyone out there think it may be a TPS? Does anyone out there think plugging in an ODB2 reader in would give us a trouble code? There's no check engine light on right now.

Anyway....hittman needs to tow a trailer 3200 miles next week so if someone has a suggestion, let er rip.

 

What engine is it?

 

I would check your grounds and the intake hose in between the Maf and TB if the hose has a small leak it can make the truck stumble.

 

TPS passes the resistance test using an ohmmeter and is fine. No apparent leaks in the intake hose either. Noticed that it is using up oil (not leaking on the ground) and idles a bit rough too. I'm beginning to think the worst, but hoping it's not a compression issue. I'm going to take her in to see the doctor tomorrow...hope it's good news.

 

I'll post ths fix for hittman, because he's a slacker.

The problem was a cracked plug. Now she runs fine.

JB

 

sorry for being a slacker, but a functioning toyota can cause anyone to spend less time at their computer

 

Could be a lot of things, is it timed correctly?

Nevermind I see you got it.

 

Ha ha ha!! Just busting your b*alls. :-)