I don't know what else I should do?

[Silicon 70]

Will not hold constant speed...HELP!!

Like the title says. I've used the search feature to find out what the hell is causing this problem. First here's the specs.

1987 4Runner 22RE(automatic)
basic tune-up done, ya know spark plugs and all that good stuff(about six months ago)
TPS and AFM have been replaced(TPS 2 months ago,AFM yesterday)
Techron added at every oil change.

2 months ago the fuel line had burst under the vehicle. PO had rigged it up with hoses where the fuel line broke. I took care of this problem by fabbing up hardlines that looked just like OEM, same diameter and everything.

The problem has been occuring lately when the truck is in operating temp already and I'm driving it. It will not hold a constant speed. It feels like its confused on what gears to shift into and the rpms keep on fluctuating. I don't know what's causing it, but I really need help in fixing it. I really need to order a FSM for this truck.

My last guess is its the fuel filter, but could a dirty fuel filter cause the truck not to hold a constant speed? Shouldn't the problem occur even when the truck is not in operating temp yet?

Again thanks for the help.

 

[KliersLC]

Fuel filters are cheap and that is where I would start.

OTOH, if it doesn't do it when locked into gear (ie lock it in 2nd) It could be a tranny issue. Dunno about the autos on those years, but it should have some sort of modulator to control shifting and/or a kickdown cable. How is the overall condition of your tranny? fluid color and level, miles, mods, etc.

But I'd start with the fuel filter..

Good Luck,
Dan

EDIT: also, what was the cause of the fuel line breakage? Off road use or just plain line failure? If it just failed, it is likely that you have quite a bit of corrosion sucked up into the filter and that makes that option even more likely.

 

[Silicon 70]

If its the fuel filter, then why does the shuddering only happen when the car has reached operating temperature? Shouldn't it happen when I start the car in the very beginning?

The line failed because the PO put rubber tubing in between the lines and had them double clamped. So when it failed, I had to make a new one.

A friend of mine says its the EGR. After some more looking on the internet, this is looking more like the culprit. I'm going to take mine off and clean it with some carb cleaner and see if it helps.

 

[MiniNate]

egr seems like a likly culprit but he is right replace the fuel filter, 5$ at napa will get you one, also on an 87 auto transmission you should think about replacing the transmission filter and flush the tranny fluid.

p.s. when the fuel filter in my old 85 fj 60 went it only acted up after driving about a mile or so. =P

 

[Silicon 70]

egr seems like a likly culprit but he is right replace the fuel filter, 5$ at napa will get you one, also on an 87 auto transmission you should think about replacing the transmission filter and flush the tranny fluid.

p.s. when the fuel filter in my old 85 fj 60 went it only acted up after driving about a mile or so. =P

I'm going to test the EGR valve per FSM instructions and see what I come up with(Got a FSM today on craigslist for $5)

The rebuilt auto tranny was serviced 2000 miles ago, that should remove it as a culprit. I'll reveal my findings on Saturday.

Does anyone have the part number for EGR valve for 87 runner with a 22RE?? This would be a big help in case I need to buy one.

 

[KliersLC]

CruiserDan does... but he's probly gone home for the day.....

Call your local toy dealer

 

[Silicon 70]

I called my stealership and they wanted $205 for it. I went to toyotapartscheap.com and entered the same part number and it came out to $145. I'll order it from CDan though just because he's the Parts Shaman.

 

[Silicon 70]

Confirmed, it was the EGR valve. Came to the conclusion after, doing the diagnostic as the FSM said.

 

[KliersLC]

Cool,
I am glad you got it figured out. I'll file that little tidbit away for future use.
Cheers,
Dan

 

[MiniNate]

Good show man

 

[Silicon 70]

I thought this thread would be over by now, but after changing the egr valve the hesitation has now just become very slight. So now I'm left with finding some bad hoses.

 

[KliersLC]

Did you check your fuel pressure?
Your pump could be on the way out...

Also, your plugs might have gotten fouled, it might be worth it to pull them and clean them if needed.

Confirm your timing is spot on and if none of that helps, you might look at adjusting your valves......

Good luck,
Dan

 

[Silicon 70]

I've got my work cut out for me, I'll post what I find on the weekend.