1989 FJ62 Intermittent Engine Problem (1 Viewer)

[drcdan]

The FJ62 has 240,000 miles and is my daily driver. It runs great MOST of the time but every once in a while will not rev above 1500 to 1800 RPM. If you press on the gas pedal it pops thru the intake and loses RPM. This usually happens when accelerating from a stop but has happened at highway speeds. It will stay that way for a minute or so and then go right back to smooth running and accelerating. Any suggestions on what I should be adjusting or replacing? Thanks for your help. Dan Carr 239 272 2741

 

[IBFJ62]

I'd say start with a new fuel filter.

 

[morganism]

Clean the EGR valve, it can cause weird problems if jamming open.

Those have an MAF too right, those can build up a coating, and stop reacting quickly. Gotta be gentle with them.

Watch if dash lights do weird things when it happens too.

 

[drcdan]

Thanks for the reply. I replaced the in tank fuel pump and filter sock, the fender mounted fuel filter and the fuel pressure regulator. No change

 

[drcdan]

Clean the EGR valve, it can cause weird problems if jamming open.

Those have an MAF too right, those can build up a coating, and stop reacting quickly. Gotta be gentle with them.

Watch if dash lights do weird things when it happens too.

Thanks for those suggestions, I'll do both this weekend. I don't get any dash lights when the engine is acting up.

 

[morganism]

EFI relays can cause weird problems.. Are you carbed tho?

Fj62 intermittent starting issue!!!!!

Does the '88 fj62 have a engine compartment relay /fuse block? On 4Runners, those blocks have a feed that comes up and in thru the bottom, and the connector is VERY susceptible to metal fatigue. Try (gently) to wiggle, and see if any change.

Main Alt wire getting warmer than seems normal? If so, clean and reseat coil holdown cage and bolts. Major ground and if it helps, and seperate ground wire from ignitor case to a solid body ground. 100 series added that wire as stock.

 

[Prairie Swamp]

Before getting the parts cannon out I would look at the trouble shooting section in the manual and start testing.

In particular the air flow meter (NOT an MAF on the 62) and the throttle position sensor. And EGR as mentioned.

 

[mwebfj60]

I was thinking the same as Prairie Swamp. Start running through the FSM tests and check codes.
Testing the TPS in the vehicle, it's almost impossible to get the feeler gauges in between the throttle stop screw and throttle lever for the IDL to E2 checks but it sounds more like the VTA to E2 connection could be the issue as the throttle is advanced (if the TPS is the problem). That is pretty easily checked in vehicle as you can just put the meter on the VTA and E2 pins then rotate the throttle. There is a base resistance with throttle at idle setting and a max resistance with throttle fully open. Watch the resistance as you slowly open the throttle all the way. As you increase the opening of the throttle, the resistance should smoothly increase with no breaks in continuity. As you slowly close the throttle from fully open, the resistance should smoothly decrease with no hangups or opens. One way for a TPS to fail is it no longer springs back so if you push on the gas and then let off, it doesn't immediately follow the throttle and kind of hangs open.
The IDL to E2 check can still be done in the vehicle. A rough check would be to make sure there is continuity at the idle setting then just open the throttle a little and make sure it goes to open.