Ok, just bought my first yota, 88 with the 3.0 5spd.. I have a bit of a problem with it. It has a rough idle about 900rpms, and stumbles. when i give it gas its great, i mena, runs fantastic, it is a little gutless but i guess thats what supposed to be expected with these (4 inch lift 33x12 BFGs stock gearing).. I went ahead and checked all the plugs, they look good, replaced the wires, checked cap and rotor, theyre good.. I'm kinda lost from there on this rig as im not very familiar with it.. anyone point me in the right direction??


TIA

Mike

PS No Check engine light, runs nice and cool, problem stays weather its hot or cold...

 

Hard to say with an EFI system. There's a number of variables....vacuum, electronics, and all.

Here's the troubleshooting guide from the FSM. Follow the chart according to symptoms and numerical order.
http://personal.utulsa.edu/~nathan-b...63troubles.pdf

Start by testing things with a multimeter and gauges, if you have any of that at your disposal. The easiest place to start would be vacuum lines, though. With the motor running, spray ether wherever you can reach. If there's any leaks the motor will rev. Inspecting the throttle body for build up is easy, too. Cleaning it is always recommended.

If while following the TS guide, you come to any part in question you are not familiar with, run a search using the part as the keyword and you will turn up lots of info on any of it.

 

Thanks, thats a great chart.. I'm gonna try blocking off the EGR today as it seems alot of the same symptoms could be created by that also...

 

If its idling a bit to low you can always ust adjust it a little bit by adjusting the idle screw on top of your throttle body. I use to have the same problem I could never get my truck to idle right it was idling like an old camaro. Just let it warm up and try to get it to idle at about 1000 or so it seemed to work pretty good for me. Now more chugging and such. But yeah do the ether thing to just to make sure theres nothin else wrong.

 

I have a 1989 3.0 SR5 had the same problem and I am still working on it. I was told to check compression which I new I should and sure enough #6 cyl. was running about 15lbs. it did just as you described. have not had a chance to see if its valves,piston ring or gasket yet but either way the head has to come off. Going to do a leak down test and go from there.Good Luck Rob

 

Often injectors if after replacing the maintenance items. Berrymans from Wally World or your local parts store is great for the price. If you have half a tank or more, dump two cans in and run it empty. It will clean the injectors but will not fix a tired injector. May be a vacuum leak. May be....well...a lot of things too. Start cheap and easy and work your way to expensive and pain in the a$$ to do.

My $0.02

 

seafoam it
if you dont know what it is run a search
it helps a lot with high millage engines