1988 22RE engine surges with moderate accelerating

[LostinDartmouth]

hi there.....Any helpful advice is appreciated:

22re from a 1990 in a 1988 4runner. Idles well. Runs well. However, when i accelerate with moderate pressure on the peddle the engine starts to surge. The surge is not so significant that the engine misfires, but you can feel it through the truck. If you accelerate very quickly, the problem doesn't exist. Only on moderate acceleration.

My thoughts are:
1) fuel pressure is too low (maybe a vapour leak at tank since I sometimes have a gasoline odour near seal at fuel pump)
2) O2 sensor is shot.
3) bad injector.
4) throttle sensor.

I've put a fuel cleaner through the engine to clean the injectors which may have made the problem worse but I'm not sure if that is coincidence. I have also changed distributor cap, plugs, wires, and rotor.

Any advice from 22RE folks???

Thanks Paul

 

[fourwd1]

Have you checked for error codes in the ECM?

Was this motor running OK before you installed it?

 

[LostinDartmouth]

Hey Fourwd1:

The 1990 engine ran well before and after installation. Problem has cropped up in the past 3 weeks.
Have tried to retrieve ecm codes with no luck. Jumped T and E1 terminals but get no light on the check engine light at all.

Thoughts?

 

[LostinDartmouth]

A follow up: I think I found the problem. When changing out the sparkplugs, leads, rotor and cap, the timing was somehow impacted. I've advanced the timing by 1mm (ie turning the distributor) - the problem has nearly vanished. In addition, it has given me much more power.

As with most fixes....time will tell.

Thanks Paul