The Classic FJ60 "Stumbling/Hesitating Acceleration/Running Problem (2 Viewers)

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OMG I'm not alone! since i'm not very mechanically inclined, i'll be sure to let the shop know what to look for. pretty sure it's an exhaust leak. smells like it, anyway.

Just another thought: If your EGR line is leaky (depends where) to much air could be drawn in into the intake manifold, leaning out the mixture.
 
Great Thread

Well I was getting 8-9 MPG on my '83 FJ60 and decided to buy a used carb off E-Bay so I could rebuild it and if I screwed it up I could always put the old one back on. Got the rebuild kit and went to work, ended up running pretty well but hesitated and stumbled at lower revs. The former owner had messed up all sorts of vacuum hoses, so I got that all straightened out after a few hours. Valves were on backwards, the A/C idle up was connected directly to vacuum so it was on 100% all the time. The Choke breaker and opener were switched around, all sorts of things had been done wrong. I spent about 2 hours yanking all the vacuum lines and installing new ones to the proper spots. Cleaned out the HAC filter ( not too bad since my cruiser had never left the road before I owned it) and even disconnected the Tach. Still hesitated and stumbled but ran better than ever at WOT with the new secondary working properly. Then I found this thread and the Golf Tee fix. Smooth as silk now and just did 17.67 MPG on the highway. This thing actually feels peppy now.
No emissions laws here, so looks like its fixed.
 
FJ60 Stumbling Fixer Upper

Good Morning, just wanted to thank all the contributors to this thread, very helpful.

My trusty "turd bucket" FJ60 developed these symptoms, here is what worked for me:

1. Careful inspection of "Idle Control Valve/Sensor" wiring showed that the ground (white wire) was frayed. Cruiser had been de-smogged by previous owner.

2. Unplugged smog computer behind driver left foot kick panel.

3. Grounded white wire from Idle Control Valve to screw on Troll Hole Carburetor (these are just plain awesome carburetors by the way).

4. Turned key to ON position, uncoupled and re-coupled green Idle Control Valve coupler, distinct click noise.

Rig runs strong, no dying at intersection issues.

Value add, removed vacuum advance hose from distributor and reset timing to 12 degrees total.

Runs better now.

Next step will probably be a Man-A-Fre DUI type distributor with manual (de-smogged) advance (please no boo'ing).

Thanx again, one and all
 
same problem on my 85 ... sounds like i have a long list to go through and figure out
 
Zach - start with the easy stuff and work your way through it. If nothing else, take a look at the vacuum lines and if they look as though they are original it may be worth your while to go ahead and replace. Places like boostcontroller.com sell the correct lines (3mm and 5mm ID) for quite cheap and you can basically take the line off, remembering where it went, and cut the new line to size (slightly longer to allow for some shrinking).

There are other diagnostic threads out there about cleaning the EGR and stuff like that which will help things out. Try running the diagnostic "Golf Tee" trick to see if the EGR is causing issues, and then from there start working through things and doing stuff like running a can of Seafoam through the system.

Do you have a FJ60, FJ62 or something else with a 2F engine?

Also, don't forget that you have some great shops in your area (assuming you are in the Sac are) like Georg at Valley Hybrid (OrangeFJ45) in Stockton. These guys are normally more than happy to spend a bit of time on the phone with you trying to troubleshoot and are great contributors to the forums.
 
i picked up an 85 fj60, love my bj40 but needed some more room. i've replaced all the vacuum lines , the pcv valve and ran a couple bottles of sea foam through the carb and the gas tank . it ran fine for a while . i can cover the air intake and the idle doesn't change , so i think i fixed all the vacuum issues . it just wont start on cold mornings . then sputters out every once in a while at stop signs ....i replace the fuel filters . I'm starting to think fuel pump and actually take the carb off and clean it ... maybe start on the egr . i love the forum you guys are a huge help !
 
Thread revival. 82 FJ60, 88k miles, 14mpg highway on first trip home. Idles fine, runs great except it feels like the slightest amount of fuel starve or just not delivering all she's got (not sure what to call it) at the top end of 1rst and 2nd gear. I then bypassed the EGR to test and noticed improvement in 1rst and 2nd gears except now I have pinging under load at hwy speed around 3k rpm. Is this an either/or - I can be happy with bypassed EGR and no hesitations or live with pinging? What should I check next...other than study the FSM emissions manual :) With functioning EGR the hesitation is so slight that a toyota dealer mechanic (though not versed in FJ60's) said the hesitation was in my imagination...it very well could be, my first 60 so not sure what normal is :)
 
Thread revival. 82 FJ60, 88k miles, 14mpg highway on first trip home. Idles fine, runs great except it feels like the slightest amount of fuel starve or just not delivering all she's got (not sure what to call it) at the top end of 1rst and 2nd gear. I then bypassed the EGR to test and noticed improvement in 1rst and 2nd gears except now I have pinging under load at hwy speed around 3k rpm. Is this an either/or - I can be happy with bypassed EGR and no hesitations or live with pinging? What should I check next...other than study the FSM emissions manual :) With functioning EGR the hesitation is so slight that a toyota dealer mechanic (though not versed in FJ60's) said the hesitation was in my imagination...it very well could be, my first 60 so not sure what normal is :)
Could it be the timing? Give the distributor a twist and see how she runs. 7degrees BTDC is what the manual calls for but some 2Fs seem to like running around 9 to 11 degrees BTDC. Mine seems to prefer around 9.
 
The FJ60 I had had the same problem.
There are two likely causes:
1. an EGR age related matter where the EGR for some reason opens to early and/or to fast.
Hence you disconnect the EGR (higher NOX) the problem seems to vanish.
Alternate Solution: reduce the vac flow to the EGR so it opens later and slower (You still can pass CA smog with that!) by means of an adjustable hose pincher or get a inline valve or flow restrictor from a drip irrigation system. This is what I used: http://www.rainbird.com/landscape/products/dripEmission/XeriSpraysMisters.htm

2. If you have a leak in one of the membranes of the dual chamber vac advance/retard (by the distributor) this will cause the stumble as well.
Simple to check: suck on the advance part, does it hold? If not does it hold if you plug the retard port?

Either and/or both in combination create this stumble phenomenon.

Alternately test when stumbling occurs: pull gently the choke, does it disappear?
If yes, it's not due to the "enrichment" but more so to the higher vacuum affecting the aforementioned.

Ex LC'er
 
reduce the vac flow to the EGR so it opens later and slower
dorcom, do you remember which vac line you added this 'flow restrictor' into? Was it one of the ports (P, Q, R) on the EGR Valve Modulator?

Thx.
 
What should I check next...

Could it be the timing? Give the distributor a twist and see how she runs. 7degrees BTDC is what the manual calls for but some 2Fs seem to like running around 9 to 11 degrees BTDC. Mine seems to prefer around 9.

Also might consider checking to see if the plastic OEM distributor stop pin bushing has deteriorated. If so, replacing it with an aluminum mod will ensure that the governor weights start/stop at the correct position in the dizzy...see:

https://forum.ih8mud.com/threads/distributor-stop-pin-bushing-dimensions.784670/
 
...after the modulator, in the vac line that goes to the EGR.
You can test your EGR by sucking on that line and the idling engine should stall and stop.
(Careful thought should your EGR have a membrane leak you suck in some nasty s***!)
 
Yes, that's the one.
Alternately you can plug it also.
You will get better gas mileage and power.
Just don't forget to revert it should you need to do a smog test.

All the EGR does is recirculate a portion of the exhaust to lower combustion temperature.
NOX emissions do not form in significant amounts until the combustion temperature reaches 2800 F.
Once that threshold is passed, however, any further rise in temperature results in a rapid increase of NOX
 
Yes, that's the one.
Alternately you can plug it also.
You will get better gas mileage and power.
Just don't forget to revert it should you need to do a smog test.

All the EGR does is recirculate a portion of the exhaust to lower combustion temperature.
NOX emissions do not form in significant amounts until the combustion temperature reaches 2800 F.
Once that threshold is passed, however, any further rise in temperature results in a rapid increase of NOX

Thanks. I did plug it and ran great...but I had quite a bit of pinging at highway speed. Thus my original post into this thread.
 
Check your Ignition timing BTDC.
You must use Premium Fuel! 91 which has a higher knock (ping) resistance.
The best compromise solution is of course the inline valve. Finely tuned you get the best of both.
 
I quickly also pinched the EGR line with surgical pliers things and noticed a huge difference down low. Rig ran great and is exactly what I have been looking for. But what is the long term effect? Is it harmful for the motor to not utilize the EGR?? I won't desmog the rig as I want it to pass smog in a couple of years.
20150616_175841.jpg

another mudder stated

"Yes.... unless you de-smog the engine correctly.
Just plugging the EGR valve only can cause detonation at higher RPMs.
The distributor advance curve is tuned (more advanced) for an EGR mixture. When EGR is removed from the air/fuel mixture, the mixture in the combustion chamber will ignite faster (and hotter) and cause the engine to ping.
The distributor ideally should be re-curved if the EGR has been disconnected."

is this true? What do you think?
 
Ok, I felt a bit awkward when I plugged with golf tees, but now valving it with drip irrigation supplies? :) We shall see, about to take a test run.

I was poking around for loose lines in the maze of rubber hoses and came across this hose below on the passenger side which is larger diameter than the rest and loose enough that it fell off. I scanned the emissions manual and did not see it mentioned. What is and and what does it do? I am guessing it should not be loose and falling off.

 
Knocking pinging detonation all the same.
Fine tune your inline valve* so you have no stumble but also no pinging. It can be done.
Well explained here:

*If you use the one suggested you may want to try sucking on one end to get a feel for how much you restrict and use some flow restrictors inline.
Alternately and better get fine adjustable needle valve e.g. http://www.mscdirect.com/product/de..._54767707024_c_S&mkwid=s|dc&pcrid=54767707024
 

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