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Unread 03-13-2013, 09:19 AM   #181
motormike24
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Quote:
Originally Posted by 86cj74.2L View Post
I've run into a lot of short cutters that don't do everything to a "T" and don't take this the wrong way. Please.......

I always run a tap in the block to clean the head bolt threads and continue Untill the tap handle twirls into the hole.

Then I oil the washers on both sides to ensure I get the correct torque without the friction holding anything up.

And for the torquing procedure I always klick the torque wrench at least three times to ensure its torque is consistent.

And before anything all surfaces get cleaned with acetone.
already done that, minus the head bolt oiling since i dont have the new head back yet... thanks!

mike

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Unread 03-19-2013, 09:22 AM   #182
Matt1981CJ7
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Hey Mike,

Did you get that CJ back together and make it home with it?

Matt
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Unread 03-19-2013, 10:10 AM   #183
motormike24
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its a YJ, but no. ive run into one issue after another. finally got a reman head for it, but then after finding 3 melted pistons, well more like one melted, and 2 that had really strange pock-marks all over them, i had to wait for my buddy's wife to ship us the remaining new pistons we have from the first time i rebuilt it. then we started thinking about why the hell a center cylinder would have detonated. im thinking that since its the closest to the fuel source, it would have been the last one to detonate. and the timing was dead nuts on 0 so that cant be it. had the intake checked for cracks, all good there. the spark plugs to all 3 cylinders had been so hot the ground strap on them melted off (hence the pock-marks on the pistons). the only thing i could think of is that when i rebuilt the tbi, i should have realized that the spring in the rebuild kit for the fuel regulator was so extremely strong that theres no amount of fuel pressure in ANY system that could have moved that spring at all, so it must have forced it to run lean as hell. aka detonation. but the super strange thing is that it detonated in lansing. we determined that because when he heard the bang sound and whatnot is when he lost power and couldnt exceed 70 mph. yet, the entire 70 additional miles he drove beyond there it didnt detonate any of the more distant cylinders it was still running on, such as 1, 2 or 6. how that works, i cant explain. but i picked up another tbi so im hoping that one will let it run rich enough. plus am going to run premium at least enough to get it back across state without detonation. such a pain in my ***. any other ideas? because my machinist pretty much told me the same thing i came up with.
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Unread 03-19-2013, 10:44 AM   #184
kappa505
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I love your tenacity.
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"Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent. The slogan 'Press On' has solved and always will solve the problems of the human race." Supposedly President Coolidge
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Unread 03-19-2013, 11:01 AM   #185
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I would guess that the damage was probably well on its way to being done before you started the TBI swap.
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Unread 03-19-2013, 01:45 PM   #186
Matt1981CJ7
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Quote:
Originally Posted by CSP View Post
I would guess that the damage was probably well on its way to being done before you started the TBI swap.
Nice to see this thread finally come around to the point I tried to make earlier....way earlier.

Mike blamed the previous carb for causing detonation in one cylinder. I questioned that, but Mike was adamant the carb was to blame. Now, he has detonation in multiple cylinders with a TBI. So, are we to assume the TBI is to blame? I doubt it.

I really wasn't trying to stir the pot earlier (well, maybe a little), but I've suspected Mike has been chasing the wrong problem all along. I know he will get it figured out, eventually.

Matt
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Unread 03-19-2013, 01:46 PM   #187
motormike24
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Quote:
Originally Posted by CSP View Post
I would guess that the damage was probably well on its way to being done before you started the TBI swap.
turns out the machinist found that the bolts had snapped off (the bolt heads anyway) for 2 of the top intake-and-exhaust-to-head bolts, which he believes accounted for the extra lean condition. however, im not entirely convinced. yes the intake is heavy, and yes a missing bolt or 2 on the top row COULD cause a very little bit of air to seep inbetween the manifold and head, BUT, if that was happening how did i have 20-22 in Hg on my vac gauge be4 i left detroit? then again maybe it just expanded with the heat of the long drive and conditions changed mid-trip idk. but it couldnt have been anything from before i did the tbi swap. i COMPLETELY rebuilt the engine, then ran that motocraft carb for maybe 20 miles, and decided to park it and do the tbi swap. and its had 4000 miles on it since. i dont buy that theory that 20 miles caused a problem 4000 miles later. im praying to god that with the combination of a different tbi, fresh reman head, new bearings, piston rings, pistons... it should not do this again. if so, its going to the scrapyard and we are building his 318 dodge truck instead.

mike
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Unread 03-19-2013, 01:59 PM   #188
CSP
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I assumed that it hasn't run many miles at all on the TBI setup, given the fact that this thread has been nothing but problems with it. It was allowed to run that many miles with it running absolutely like crap? How many miles were on it when this thread started?

Gotta tell ya, this install sounds like a complete clusterf*&k. Same thing goes with the troubleshooting, despite a lot of good advice given to you on how to properly troubleshoot. I've stopped trying to figure it out for that very reason.

And yes, you can pull good vacuum with a leak like that at the manifold/heat junction point. That's why you don't try to chase down a vacuum leak by just looking at a gauge. All the symptoms, primarily the high idle, have been pointing to that very leak.
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Unread 03-19-2013, 04:13 PM   #189
motormike24
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it only ran like crap at idle, and its his only running vehicle, so yea he had to run it. im in the middle of putting the engine back together with all new pistons/bearings/gaskets/head/exhaust manifold right now. so will let ya know how it does after its complete. thanks
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Unread 03-19-2013, 04:32 PM   #190
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Quote:
Originally Posted by motormike24
it only ran like crap at idle, and its his only running vehicle, so yea he had to run it. im in the middle of putting the engine back together with all new pistons/bearings/gaskets/head/exhaust manifold right now. so will let ya know how it does after its complete. thanks
I replaced a perfectly good carb back in 2002 or so only to find out it still ran like crap after the 300 dollar reman carb acted the same way. I was so frustrated with the carb or carbs. I was preparing for a TBI instal.

So I warmed up the engine and started spraying the non flammable brake cleaner I had at everything. When I hit the intake to head mating surface for 4&5 cylinder it sucked up the brake cleaner as fast as it was comming out the can. And then stalled it.

That's when I started paying attention to the manifold bolts and noticed they loosened up on me every so often.

I went and got a two piece manifold gasket set from felpro and went junking to collect all the cupped washers I could find for the bolts. Haven't had a problem since.

I also learned how to make the BBD work because 300 dollars was a waste of money for what's under the top plate. And never concidered going TBI since.
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Unread 03-19-2013, 06:22 PM   #191
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thats awesome. but a bit late for me as the tbi conversion is already done and the money already spent. if that theory is correct, then it should run perfect after i finish putting it back together. ive got the pistons and bearings and oil pan and head on, just have to torque head bolts. i bolted the intake/exhaust on the head be4 i set it on the block just to make sure that when i torqued them down they were both flush and sealing properly. and yes i used the piece felpro gaskets that came with the felpro head set. should have it running in and hour or so. praying that this is the end of my nightmares. on a different note, does anyone know which of the many 2 piece headers out there are actually worth buying? we want to eventually run true dual exhaust and found several different kinds of headers that are 2 piece and come out to 2 separate collector pipes.... but dont want ebay junk. thanks

mike
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Unread 03-19-2013, 11:20 PM   #192
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so heres the update. it runs amazing. took about 30 mins to fully bleed the cooling system, but after that was done, it runs great. no more searching for idle... as long as i have the idle set at about 1000 rpm. below that it still searches between 600 and 1200 but never ever dies. cold, hot, medium, it doesnt matter. but im assuming the not dying part is because i must have had an intake leak for awhile as you all mentioned. so my bad on not believing that. im sorry. however, it still puzzles me that even with the new tbi unit and another freshly rebuilt motor, it cannot seem to find a happy idle below 1000. timing is dead on still at 0 degrees base timing. no check engine light anymore. doesnt seem to sputter out the tailpipe nearly as bad even when idling at 1000 as it used to pop and sputter a lot. instant throttle response as its always had even when running like crap. but... my main concern is what can i do to ensure that im not going to detonate another piston on my 200 mile journey back across the state in the morning??? i cant have any possible chance of that again. any suggestions beyond running premium fuel on my trip? thanks in advance

mike
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Unread 03-19-2013, 11:41 PM   #193
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With your scanning software you verified the temp sensor (engine coolant temp sensor) reads 195?

Also what are you doing to not let it idle below 1000? Adjusting the screw on the throttle plate? If so those are not suppose to be used like a curb idle screw on a carburetor. They are set factory and if one experiences a idle problem its suppose to be fixed.

If you adjust the idle back down slowly Untill it just starts hunting and stop will it settle out?

My friends truck has a screwed up idle for two weeks after he disconnects the battery. Even stalls for him in the beginning.

You have a aluminum intake? It has a heater under the opening for the carb if it is. I would recommend hooking it up. Especially no that you have a injector spraying down at it. Also that heater could be a vacuum leak if the seal is toast.
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Unread 03-20-2013, 09:01 AM   #194
motormike24
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Quote:
Originally Posted by 86cj74.2L View Post
With your scanning software you verified the temp sensor (engine coolant temp sensor) reads 195?

Also what are you doing to not let it idle below 1000? Adjusting the screw on the throttle plate? If so those are not suppose to be used like a curb idle screw on a carburetor. They are set factory and if one experiences a idle problem its suppose to be fixed.

If you adjust the idle back down slowly Untill it just starts hunting and stop will it settle out?

My friends truck has a screwed up idle for two weeks after he disconnects the battery. Even stalls for him in the beginning.

You have a aluminum intake? It has a heater under the opening for the carb if it is. I would recommend hooking it up. Especially no that you have a injector spraying down at it. Also that heater could be a vacuum leak if the seal is toast.
yes i verified its reading between 190 and 200. and if i have the idle screw set to 1100 rpm, it idles great. but if i go below that it hunts badly and sometimes stalls. however, i found that if i advance the timing to 10 degrees or so, it runs amazing and then i can idle it down to 700 no problem. so what would that mean. and the seal for the intake heater is brand new, and not leaking. im very terrified of detonating another piston on my way home. so any suggestions on where to go from here would be greatly appreciated.

mike
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Unread 03-20-2013, 09:14 AM   #195
jeepardy
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Just want to make sure this is right. You have 0 deg timing with the bypass. It should then jump 8-10 deg with bypass hooked back up. If you set timing to 10 deg, it should then be 18-20 deg with bypass connected. Is the ecm doing this?
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