FJ62 Hesitates, no power, rough idles at times (1 Viewer)

[jonheld]

No one has mentioned the pre-filter on the fuel pump pick up. They are typically a 100K mile item that no one knows is there. On an 80 they are simple to change, but on a 62 you need to drop the tank.

I suspect this simply because of the potential for crap build up in the tank, the age of the vehicle, and the fact that you say it idles OK. Sounds like fuel starvation to me. Ignition problems tend to manifest themselves throughout load/rpm range. Fuel problems tend to be more load related.

 

[acoen]

No one has mentioned the pre-filter on the fuel pump pick up. They are typically a 100K mile item that no one knows is there. On an 80 they are simple to change, but on a 62 you need to drop the tank.

I suspect this simply because of the potential for **** build up in the tank, the age of the vehicle, and the fact that you say it idles OK. Sounds like fuel starvation to me. Ignition problems tend to manifest themselves throughout load/rpm range. Fuel problems tend to be more load related.

Ok guys....i have it idling, I cleaned the IAC again, better than before. Changed the coolant temp sensor cleaned cold start injector, checked for vacuum leaks and adjusted timing. I have to say seeing the timing mark is tough. I can barely see the damn pointer, let alone the timing mark. I placed the jumper and lined the pointer with the timing mark. It seemed to have ran a little better, but I have no power past half throttle. Now it is low on fuel around 1/6th tank and it will hardly run, but it will idle. I haven't had the chance to go to the wrecking yard to pick up a banjo fitting and hose but I did check flow, but I don't think there is much pressure. Should be 33psi and I can put my thumb and finger over the banjo fitting and can pretty easily stop the flow....That for sure isn't right. I also tried to blow back through the fuel line with my air compressor to see if I could make sure everything is clear but there must be a check valve on the pump. To be honest, I think the pump is weak and the sock is plugged. I'm all out of things to check. I checked wires and cap everything looks good. Hey at least it looks great! We'll get it, sure feels like fuel....

 

[jonheld]

There is a check valve on the pump. Spring loaded ball. When the FPR is faulty, over time it can cause this valve to stick. From the word on the 3FE list, this valve is not replaceable.

IMO, on a 62 you need to drop the fuel tank to access the pump and pre-filter. At this point you might as well replace the whole shebang. On an 80 there is an access plate on the floor and makes this very easy.

 

[mmw68]

I've been following this tread, and It sure seems like a fuel issue to me. My 3FE Fj40 was doing similar things and it turned out to be crap in the tank. Once the crap would settle, it would run fine, but after a 30 minutes the junk would clog up the fuel filter.

Replaced the tank - everything was good.

-Mark

 

[billmc]

Now I did contact the PO and he told me he dropped the tank to inspect the fuel pump. He told me the screen was collapsed, he thought it was supposed to be that way and buttoned it back up without changing a thing. Why I don't know. A collapsed fuel sock means that at some point it could have been completely clogged.

So reading back over this thread, looks like the PO told you what the problem was. I agree with Jon and Mark that this is your problem.

 

[acoen]

So reading back over this thread, looks like the PO told you what the problem was. I agree with Jon and Mark that this is your problem.

Agreed, but you do have to check everything. This makes since after checking and replacing a couple of things....The FPR and TPS were good things to replace....The Coolant sensor was shot as well. Very little fuel pressure is required to run the cold start injector...The reason why it runs and idles well cold. Once warm and in closed loop the injectors take over and need at least 33psi (at least and at idle). I'm sure now that I don't have anywhere near that kind of pressure, especially since i can stop flow with my fingers. I will replace the fuel pump and sock next week...Not a terribly difficult job (did it on my last fj62)

One nice thing is that all of the other systems checked out good. I will post photos of the rig later after I'm done and wrap this puppy up.

 

[billmc]

One nice thing is that all of the other systems checked out good. I will post photos of the rig later after I'm done and wrap this puppy up.

That's right, it should run really sweet and reliably after you get it sorted.

 

[acoen]

That's right, it should run really sweet and reliably after you get it sorted.

Thanks again for everyone's help! Today I took a break from mechanic work and enjoyed a little detailing. I should have photos up next weekend.

 

[hychamaz]

I definately feel for you as I have read this post and am definately in the same boat with my 174K 89'. After reading this post I think its the TPS (after spending an enormous amount on hastily replacing a ton of parts). I also don't want to keep replacing parts.
I havent heard any mention of O2 sensors during this thread. I know that I should change the original 174K ones but would they do anything causing these hesitation problems when they start working in closed loop (or should I stay not working in closed loop).
Good luck!

 

[acoen]

I definately feel for you as I have read this post and am definately in the same boat with my 174K 89'. After reading this post I think its the TPS (after spending an enormous amount on hastily replacing a ton of parts). I also don't want to keep replacing parts.
I havent heard any mention of O2 sensors during this thread. I know that I should change the original 174K ones but would they do anything causing these hesitation problems when they start working in closed loop (or should I stay not working in closed loop).
Good luck!

This is a strange problem, but it does act like fuel starvation. Starts up good and normal. Idles good for about 5 minutes, but as soon as I start to accellerate it falls apart. Once the Cold start timer warms up and shuts the cold start injector off, the truck starts stumbling, bucking and hesitating. A slow or lazy O2 sensor would instantly set a code.

I have not changed or checked the 02 sensors nor the computer. But I do know from the PO that the sock in the tank is collapsed. So I'm going to replace both the sock and pump.

We may want to get in touch to share thoughts....(559)916-6651 Call me any time.

Thanks,

Aaron

 

[cruiser88]

This is a strange problem, but it does act like fuel starvation. Starts up good and normal. Idles good for about 5 minutes, but as soon as I start to accellerate it falls apart. Once the Cold start timer warms up and shuts the cold start injector off, the truck starts stumbling, bucking and hesitating. A slow or lazy O2 sensor would instantly set a code.

I have not changed or checked the 02 sensors nor the computer. But I do know from the PO that the sock in the tank is collapsed. So I'm going to replace both the sock and pump.

We may want to get in touch to share thoughts....(559)916-6651 Call me any time.

Thanks,

Aaron

check the wire in the drivers rear quarter..........it is for the fuel pump. THEY do STRANGE THINGS quite often....

 

[acoen]

check the wire in the drivers rear quarter..........it is for the fuel pump. THEY do STRANGE THINGS quite often....

Is the wire behind or near the washer bag/tank or is it located under and behind the left rear wheel well? Thanks again, haven't check that yet...

 

[cruiser88]

Is the wire behind or near the washer bag/tank or is it located under and behind the left rear wheel well? Thanks again, haven't check that yet...

feel around in the area of the bag(at least that was where mine was at).

I bypassed mine altogether( i wired the fuel pump to my ac cause i no longer have ac.) . I need to do a writeup on this dermit but with everything going on i do not have time.

Once your in there it will be obvious to what it is.

 

[acoen]

I will check it out tonight. I would be nice if it was corroded or broken....Still think the pump is the culpret.

Thanks

Aaron

 

[RockDoc]

feel around in the area of the bag(at least that was where mine was at). Once your in there it will be obvious to what it is.

A new sig line for someone?

 

[cruiser88]

A new sig line for someone?

lol

 

[acoen]

A new sig line for someone?

I will just root around back there for the wet spot!

 

[cruiser88]

I will just root around back there for the wet spot!

lol.....you might find that also

 

[hychamaz]

Thanks Aaron for your number. When I get back home I will give you a call and we can hopefully chat for a bit and hopefully solve these 170K Cruiser Blues . I am currently overseas in Finland and you cant imagine the number of 60 series diesels that are over here. AMAZING!! I'm going to start my own post detailing my 89's missing and such. Good luck and I look forward to speaking. -Graham

 

[acoen]

Thanks Aaron for your number. When I get back home I will give you a call and we can hopefully chat for a bit and hopefully solve these 170K Cruiser Blues . I am currently overseas in Finland and you cant imagine the number of 60 series diesels that are over here. AMAZING!! I'm going to start my own post detailing my 89's missing and such. Good luck and I look forward to speaking. -Graham

Thanks Graham, I look forward to speaking to you...When will you be back home? Where are you located here in the states?

Talk to you soon.

Aaron