Hey there

I recently took over a 94 4runner project and I'm having some trouble figuring out why this 3.0 won't rev beyond 2k-2.5k rpms. It starts up and idles pretty nice, but when you take it for a spin it bogs down at about 2k rpm. The head gasket has recently been replaced as well as the timing belt. Yesterday I tried to time it with a timing light, and had to turn the distributor all the way counter clockwise to get it to line up with 10degrees. Wouldn't even go to 0. I made sure to warm the engine, and jumper te1 and e1. Now it idles really low. I plan on replacing all the vacuum lines at some point, but I don't hear that any are leaking. I even sprayed some ether around the engine bay, and it didn't rev up.

It's been a while since I've had a project so, I'm trying to get the creative juices flowing. I appreciate all the help I can get.

Other info:

94 4runner
manual transmission
3.0vze
new timing belt, head gasket

 

This engine has 221k miles on it too btw. I plan on keeping it a very long time, so a 3.4 swap is in the future plans. Starting probably in april, but getting this sucker going in the mean time for around town would be nice.

 

I'd start by confirming timing. You didn't mention any popping or backfiring? How clean is the intake plenum? What have you checked/tried?

 

I set the timing to the 10 degree mark, as that was as far as i could get it. I can't retard it anymore to get to 0. It currently idles very low, and if you are slowing to a stop in a gear it does pop pretty bad. Before I retarded the timing it would idle pretty nice and smooth. It revs decent until 2.5k and then it falls on itself.

I haven't checked the plenum yet. The reed valve is missing its screws and isn't sitting down evenly. I tried to get some 5mm screws in there, but I wasn't having any luck. They were all too long. I've also spray some ether around the engine bay to see if the revs increased, but nothing seemed to be leaking, other than the reed valve.

 

The rig was delivered to me with a lot of parts in a bin, as well as bolts in a little baggies. This is my first toyota, so it definitely is a puzzle. I just hope I don't offend anyone with silly questions. I appreciate any and all help guys!

 

Is it possible that when the new timing belt was put on that it's off a tooth? This weekend I will get some time to take a look at it. Are there timing marks on the sprockets and pulley to use if it happened to marked improperly?

 

The marks on the sprockets and crank pulley are the only ones that are definitive. The marks on the belt are just there to help with installation, but won't necessarily line up once the engine has turned a few revolutions.

 

Ok great. I will take a look this weekend and see if everything is lined up correctly. Should be easier than the ford rangers, they have multiple markings lol.

 

I did my own timing belt and water pump, everything went smoothly. I took off and re-did my timing belt 3 times because it kept jumping a tooth, I thought I had it on the 3rd time, but the truck ran really rough, lack of power, hesitation with acceleration...Took it to a mechanic because I didn't want to tear it apart for a 4th time, and he confirmed that I was off 1 tooth on my cam shafts, he corrected it and truck runs a lot better, able to get timing set at 12 without distributor maxed out clockwise like before. Now my issue is my clutch is slipping (engine revs up, but no increase in speed) so gotta work on that next.

 

Yeah i saw your thread, and thought that that's probably what is going on. I bet the belt is off a tooth. I still haven't had time to look at it, been doing maintenance to my other cars before the fall comes. But I have tomorrow off and plan to take it apart and try putting the belt back on.

 

How difficult is it to work with the belt tensioner? I haven't had to work with this kind of design yet. Do I just pull back on the rod with some vice grips?

 

I think I made a little progress today. I think the driver side cam gear was off a tooth. I readjusted everything, and tried to fire it up. I had to eye ball the distributor to get it to start up. It seemed to start easier, and it revved pretty decent in neutral. But once I took it for a spin, it would buck pretty bad and wouldn't rev passed 2.5k.

Going to try to time it tomorrow with a light and see how that helps.