Fj62 runs great with advanced timing, awful without (1 Viewer)

[partytime]

Hiya friends, long time lurker, first time poster. My truck runs great with no audible detonation or pinging with the timing advaned to 21. However it won’t pass smog unless the timing is at 7 degrees, and adjusting it that low or even down to 12 makes it bog and die under load. The truck idles fine and otherwise seems great and passes all smog test EXCEPT the timing with the timing way advanced like this. Since there is no timing chain/belt in the 3fe my only assumption is dizzy off by a tooth, however i would think that i wouldnt be able to make it run smoothly with the advanced timing if that was the case. Anyone got any other suggestions?

I seem to have the exact same problem as this guy - Timing a 3F-E - Pirate4x4.Com : 4x4 and Off-Road Forum
I think the truck should run like s*** if the timing was truly 20+ degrees advanced

 

[BlackCat]

If you can get your timing into spec, it’s not off a tooth. When I bought my 60 it was off a tooth, and I could only get it to about 14 degrees before running out of adjustment.

 

[partytime]

My valves are pretty loud, should I do a valve adjustment first before worrying about fixing timing?

 

[partytime]

Ok so I did a valve adjustment, truck purrs like a kitten now, sounds much better There was a lot of sludge on the valve cover and on the rockers, I cleaned a bunch off as best I could, but will probably get back in there with some solvent....

I was having trouble finding TDC on #1 cylinder, so I hooked up a bump starter and looked in the flywheel inspection window. Turns out the PO (who will surely burn in hell) had painted 3 white circles in random places on the flywheel, including one on the actual BB. Why!?!?!?!? No wonder it was so hard to find!!!! I scraped the bogus paint marks off with a knife, and left the one on the actual BB, and painted a thin line at the TDC marker.

I also noted that the distributor rotor points at the #1 wire at TDC, so I don't think my distributor is installed wrong.

So I tried timing again with the correct mark on the BB, I retarded the timing to about 10 degrees BTDC according to the timing light (with the jumper) and I still have the same symptoms, with the timing down around 10 the truck is gutless and barely moves at low rpm, totally undrivable. And again when I bump it up to 20 she runs great.

Still searching for a cause....

 

[Bryan062087]

Did you put a paper clip or a test wire to connect the TE1-E1 terminals in the computer diagnostic port in the engine bay before checking timing?

 

[partytime]

Did you put a paper clip or a test wire to connect the TE1-E1 terminals in the computer diagnostic port in the engine bay before checking timing?

yup, jumped te1 to e1 with a paperclip, and confirmed that the check engine light flashes after its jumped.

 

[LAMBCRUSHER]

You are using a timing gun to give you your timing value, right? Have you tried a different gun? Instrument could be fubarred...

 

[LAMBCRUSHER]

And try another dizzy, if you can borrow one... only other thing is ecu...

 

[Seth S]

Does the vacuum advance in your dizzy work?

 

[Spook50]

Hiya friends, long time lurker, first time poster. My truck runs great with no audible detonation or pinging with the timing advaned to 21. However it won’t pass smog unless the timing is at 7 degrees, and adjusting it that low or even down to 12 makes it bog and die under load. The truck idles fine and otherwise seems great and passes all smog test EXCEPT the timing with the timing way advanced like this. Since there is no timing chain/belt in the 3fe my only assumption is dizzy off by a tooth, however i would think that i wouldnt be able to make it run smoothly with the advanced timing if that was the case. Anyone got any other suggestions?

I seem to have the exact same problem as this guy - Timing a 3F-E - Pirate4x4.Com : 4x4 and Off-Road Forum
I think the truck should run like s*** if the timing was truly 20+ degrees advanced

Wait, Commiefornia won't let you pass smog if your timing is advanced?

 

[partytime]

You are using a timing gun to give you your timing value, right? Have you tried a different gun? Instrument could be fubarred...

Yup, i have the gun set to 0, connected to plug wire #1, and the BB is centered on the timing mark in the timing window. At 7 deg btdc the truck will barely move under load, it will rev high just fine.

Does the vacuum advance in your dizzy work?

Does the fj62 have vacuum advance on the dizzy? I'm not sure how to test this and don't see any reference to it in the fsm... can you direct me to the correct page, or place to look?

 

[EscapeWagon62]

Two items:
1. Check your throttle position sensor. It may be that it’s set way low (rotated counter clockwise to the point that the connector is facing around the 7 o’clock position on a clock). The only way to make it not stall is to have way advanced timing. Worth a shot.
2. The probable reason there were extra marks on your flywheel....put there so the PO could manually rotate the flywheel from underneath the truck with a screwdriver and line up 7 degrees BTDC and TDC by lining up the extra marks. I did that on my rig. Saves time when doing valve adjustments.

 

[partytime]

Two items:
1. Check your throttle position sensor. It may be that it’s set way low (rotated counter clockwise to the point that the connector is facing around the 7 o’clock position on a clock). The only way to make it not stall is to have way advanced timing. Worth a shot.
2. The probable reason there were extra marks on your flywheel....put there so the PO could manually rotate the flywheel from underneath the truck with a screwdriver and line up 7 degrees BTDC and TDC by lining up the extra marks. I did that on my rig. Sabes time when doing valve adjustments.

1. TPS position looks good, plus wouldn't this affect the driving all the time? Either way I broke the clip so I guess I need a new one now anyway...
2. Oh ok, not sure why you would make 3 marks though... 2 might make sense

While messing with the TPS I managed to break the wire harness clip, the plastic is 30 years old and extremely fragile i guess. Now I have another problem it seems...

 

[partytime]

My idle is at 650 when i am in gear (as indicated on the tach in the instrument cluster), but around 750 (even when warm) in Park or Neutral

 

[partytime]

Thanks to this post - Wanted: Plug that connects to Throttle Position Sensor I will order a new connector, and zip tie the exiting one on for now. Might order a new TPS as well, part number 89452-28030 but they're insanely expensive for oem! 100+ bucks for a simple induction switch, looking at the schematics I may try out a cheap knockoff first, this thing is ancient technology, even the worst electronics fabs should be able to get it right in 2019 (famous last words!)

 

[partytime]

Should also mention, I pulled the plugs during the valve adjustment, and they were all good looking, almost no dark spots, which to me implies I'm not running super-rich, or detonating with what appears to be extremely advanced timing.

 

[partytime]

Two items:
1. Check your throttle position sensor. It may be that it’s set way low (rotated counter clockwise to the point that the connector is facing around the 7 o’clock position on a clock). The only way to make it not stall is to have way advanced timing. Worth a shot.

It was TPS. I pulled the throttle body off (really hard to measure while still on) and tested the resistances per the fsm, and i could not get it into spec. Bought a new TPS at autozone, calibrated it, installed on the truck then re-did the timing per fsm and she runs great! Throttle might be a little too sensitive now actually, but should be an easy adjustment.

I owe this thread a beer if you’re on the eastisde of LA... hopefully this helps some in the future using the search button!!

 

[EscapeWagon62]

It was TPS. I pulled the throttle body off (really hard to measure while still on) and tested the resistances per the fsm, and i could not get it into spec. Bought a new TPS at autozone, calibrated it, installed on the truck then re-did the timing per fsm and she runs great! Throttle might be a little too sensitive now actually, but should be an easy adjustment.

I owe this thread a beer if you’re on the eastisde of LA... hopefully this helps some in the future using the search button!!

Glad you worked it out.