mattk

Ok i just got finished with replacing the head gaskets on my '95 Runner. Got everything back together and believe it or not it started up the first time. Really surprised me! But anyway i knew the timing was off just by the way it sounded when it started and so i got a timing light and got it all timed. I take it out on the road and have absolutely no power. When you hit the gas it just stumbles, hesitates and just doesnt want to go. I pull it back in the garage and notice i have a check engine light. I pulled the codes and got:

Code 12-no NE and G signal to ECU within 2 seconds after engine is cranked
Code 41-open or short circuit in throttle position sensor signal (VTA)

Can anyone help me out and does either one of these sound like it could be causing my problem that i described above? Any info would be great. Thanks!!!

MTL_4runner

Run a quick compression test but I would bet that your power loss is definately code related.
The test will just ensure the gasket is making good seal.

Babypig

Code 12 is probably the signal generator in the distributor going bad. Unfortunatley it seems very hard to replace this part only and toyota will have you buy the whole distributor instead. If you find one let me know where so I can get one. Could be one of the wires is bad or the connector.

41 Try adjusting the TPS first or test it with a multimeter. This will definitely affect the power the truck has. If it's bad I've got a practically brand new one that was replaced by "accident" by the dealer.

mattk

Ok from what i can gather from my Haynes manual i do not have a signal generator or a TPS. I dont know how this can be. Can you give me any more info on testing and adjusting these items.

MTL_4runner

Matt, you do have a TPS but before jumping to conclusions, check all your wiring first.
All it takes is a loose connnector or something not to be grounded and you can have similar problems.
It is worth a throrough check if you just had it all appart.

mattk

Thanks man, dummy me i knew there was a tps just couldnt find it. After i found it guess what? Yup it wasnt plugged in. Anyways plugged it back in then had to re-time it. Runs a whole lot better but now seems like i have a plug not firing. At least thats what its running like. I cleared the codes and not when i jumper the connector i get the check engine light and o/d light flashing off and on. Any ideas on that one? I will do a search and see what i can find.

MTL_4runner

Reset the codes by pulling the neg batt cable.
Then take it out for a drive and see if the CEL comes back.
If it is still on, then pull the codes again.

If you just did the headgasket, make sure to do a compression test too!!!!
I would also pull the plugs again to verify all are firing correctly (make sure to use new plugs).

The OD blinking is usually a tranny code....
....so again check if anything is out of place, loose, not grounded, etc.

mattk

Thanks MTL i will run through and verify connections again. Weird thing is the check engine and o/d light flash at exactly the same time and just keep flashing. Anyways whats the best way to make sure the plugs are firing? I did use the old plugs so i should replace them. While i have the plugs out i will do a compression check and see what happens. Thanks for the info man i probably would have looked right over the tps not being plugged in if you wouldnt have given me the heads up and double checking all connections. Thanks for the info ill let you know what i find out.

MTL_4runner

Matt, the trick is just to be thorough.
If you cover all the bases then you don't need to guess at what is wrong.
It then comes down to a process of elimination to find the problem.

Yes, do put in a new set of NGKs.
Do a compression test on every cylinder before you put each one in.
Run them for a few miles and then pull them all.

Plugs firing properly will have a nice brown color.....
....too lean will be gray/white...too rich will be jet black....not firing at all, no color and smell like gas

Babypig

The signal generator is inside the distributor. Good luck findin a new part cause they don't make them for 2nd gens as far as i have been able to find out. If you find them please let me know. You will have to buy the whole distibutor or find one that is in spec out of a wrecked runner. I am still looking for one and have been for two months. I didn't want to pay 500+ for the distributor. Hope it all goes back together and runs well for ya.