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Discussion Starter · #1 ·
Hi,

my name is Arthur. Im a gearhead from Austria which happens to have two Stealths in my collection of cars. The second project car I´ve ever gotten was a 1993 Dodge Stealth R/T Twin Turbo (Canadian edition/Delivery with KMH instrument clusters) and that was more than 5 years ago which is the source of me writing you this story with a plea for help.

Since I´ve got this Stealth, I´ve been trying to get it working again since I bought it in non-running condition. I´ve got a friend of mine who´s a master certified mechanic to help me fix this project. And here´s how it went:

  • We noticed there´s an aftermarket alarm device installed
  • We removed the aftermarket alarm, yet the car didn´t want to start
  • My mechanic friend got really annoyed by not finding the issue, and he quit on helping me
  • By luck and chance I found out the problem(s) and fixed the car. It started the first time after more than 15 years.
  • After two minutes in indle, it started smoking white in such a condition that one could´ve used it as a smoke screen device
  • I asked my mechanic friend to help me with this problem, he diagnosed it must´ve been the head gasket.

There have been lots of other issues around. A stuck fuel gauge showing it was full, even it it was bone dry, the timing was a two teeths of on one of the camshafts.

First time engine disassembly
  • We disassembled the engine up to the block and found out that both head gaskets were totally fine, and he misdiagnosed the problem.
  • We found out that the front turbo was damaged beyond repair (the interior thing broke in half) and since it was watercooled - all the water went down the exhaust and vaporised. The front catalytic converter has a big fat hole in the middle of the core. I found the remnants of the core inside the mid-catalytic converter.
  • During the assembly of the heads on the head gaskets, my friend managed to drop the head on top of the gasket, thus damaging it pretty heavily. So I´ve ordered a new set of gaskets and I let the heads checked, plained and rebuild by a professional shop.
  • We put the car back together with a new set of head gaskets (and all other engine gaskets aswell), head bolts, timing belt and tentioner. We also installed a new knock sensor since he destroyed it while working on my car.
  • The car started after somewhat of a persuation, but ran absolutely horribly, without power and with weird noises. After a while in idle, the car stopped and didn´t start at all again.
  • I checked for compression and noticed that the cylinder 5 had no compression at all.

Second time engine disassembly
  • I figured that somehow my master mechanic friend did screw up the timing or something, since the intake valves seemed to be bent on cyl 5. He denies any wrongdoing to this day and he blames the car for being "Build so shit and so hard to work on".
  • We disassembled the whole engine up to the block again.
  • My friend took the head with him and he installed the new intake valves I ordered from the US.
  • We reinstalled the heads again with new head gaskets and bolts.
  • After we put everything back together again, it didnt want to start at all.
  • We figured out that almost all of the valve lifters were broken.
  • I also perfored a compression check, just to be sure... and whaddaya know... this time ALL cylinders had no compression. Every intake valve was bent on every cylinder.
  • I told my mechanic friend what the f*ck he did wrong again, and yet again he blames the car (I paid him money to help me repair this car...). He started raging and said this car is utter trash and that I should simply engine swap it...

Third time engine disassembly (this time I did it myself)
  • I disassembled the whole engine up to the block.. again
  • I sent both heads off to a professional shop for overhauling... again (this time they performed an all-in overhaul, including new lifters)
  • I reassembled the whole engine back together again, alone by myself, with yet again a new set of head gaskets and bolts. Now with a new timing belt aswell.

For the first time in 2 major engine disassemblies, the car had compression on all cylinders again. I did it... I was very relieved (note that I am a hobby-dyi kid with no mechanical education beside learning by doing).

Now... the timing is set up perfect on both all four camshafts and the crankshaft. I do have compression on all 6 cylinders of about 9 bar. I do have sparkage, and the fuel injectors do inject, but still the car wont work. When trying to start with start-spray it does pretty loud backfires and all sorts of wrong noises.

I invited an old friend of my father, a mechanic in retirement to take a look at it. He said i did a great job in assembling it back together. He fears that the camshaft is 180° offset, which would result in backfires and the car not working.

Is it possible, or would it be the probable cause for this problem?


Any help would be appreciated.

Thanks!

1993 Dodge Stealth R/T Twin Turbo
80k Miles
 

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Welcome!

Sheesh lol that first "friend" deserves a kick in the a** for seemingly sabotaging something every step of the way hahaha...

Did you rotate the assembly a few times to ensure that mechanical timing was still correct? I would start there and verify again.

Are you positive that the camshafts were not accidentally swapped somehow between intake and exhaust?

Lastly, the typical of answer of testing for vacuum leaks... pick your poison: pressure-test and/or smoke test.

-sent from my Galaxy Note 9
 
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He fears that the camshaft is 180° offset, which would result in backfires and the car not working.

Is it possible, or would it be the probable cause for this problem?
Not if correct crank cog gear tooth was lined up to mark on oil pump when all cam gears where aligned with their marks. As bboyalan first question above was meant to ensure.

Are you positive that the camshafts were not accidentally swapped somehow between intake and exhaust?
This is a possibility as even professionals have made this mistake before. Below is cam identifying letters, yours being 93 TT would have intake marked J and the exhaust marked N.

There’s an easy way to tell if front bank is reversed. With engine turned until cam gears are on their marks, remove oil fill cap and exhaust cam lobe nose should be pointing straight out hole or slightly upwards. If lobe nose is pointing towards front of car (bottom of hole) cams on that head are reversed. Unfortunately that can’t be done to verify back bank cams. See link below from 3SX.com for better explanation.

Being a ’93 there’s always possibility of capacitor failure in ECU if they haven’t already been done. This will also sometimes cause backing when trying to start engine.
 

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Discussion Starter · #4 ·
Hi,

thank you all for your input. I built the cams in according to the 3SX Guide, so it should be OK - I´m still going to check it though.

None of the electrics have been touched. Maybe it will be worth a shot aswell..

I will keep you posted as soon as I´ve do get around checking it out.

Thanks again.

Best regards,

Arthur
 

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Discussion Starter · #5 ·
Hi all,

sorry for the late responce - it took me a while to get to it.

Soooo... I´ve checked the front cams according to White93GT and the Mitsubishi Engine Service manual. It should be OK. The lobes are pointing the right way, they have the correct markings and everthing.

As the next step I took out the ECU and dissasembled the ECU case to see if there would be some kind of damage to the circuit or something. Now Im no electrician or anything, but the board, capacitors and stuff looks all super clean and neat - there are no leaks or signs of damage.

So basically I am at following point:
  • Fuel is OK
  • it does have ignition
  • It does have compression
  • It does NOT start
  • It also does not start with start spray, it only develops one misfire (as it sounds) every few seconds if we spray in enough..., other than that it refuses to run

I´m at a loss for words or ideas at this point. Maybe ignition timing or something... but isn´t it electronically controlled by the ECU?

I´ve made some photos you can see attached and a video of me trying to start the car alone by myself (so without start-spray).
 

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Discussion Starter · #9 ·
Yes. Drain it and use fresh fuel.

Edit: There should be drain plug under the rear i think btw
Hi,

I had time this weekend so I did go ahead and tried starting it with fuel fresh from the gas station. I used the car´s in-tank fuel pump to pump it from a makeshift gas can into the fuel lines. Sadly - it didn´t start, and the gas only circulated back into the gas tank.

I tried starting it with start spray again, but nothing changed. It still won´t run even with the start spray, only developing some pretty loud and nasty backfires, with flames shooting out of the front turbocharger (the exhaust is dismantled past the turbos).

Maybe someone in this group would have new ideas? I do have a diagnostic tool for the stealth, I could try to get some reading on it. Otherwise I will have to hand the car over to a repair shop that specializes in vehicle electronics - that will definetly be expensive as hell (Im guessing 2000 - 3000 $).

I´ve made a video of my last try, as stated, and some photos you can take a look at.

Youtube video, Car start attempt
 

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You have wasted spark ... so every resolution the engine turns even with exhaust stroke the plugs will fire
Just for S*** and giggles take your CAS off turn it 180 Degrees from where it is siting on rear intake camshaft by removing it and turning the rectangular shaped piece sticking into the intake camshaft and reinstall it with doing this you will need to set ignition timing with a timing light just note that you have wasted spark also
But set the CAS as strait up and down as possible compared to the ground the car is sitting on not centered to the valve cover because it doesn't sit flat (putting the CAS at the 12 o'clock position) snug everything back down before turning key over again.... should pop off and run.... still going to have to dial in the ignition base timing
 

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You have wasted spark ... so every resolution the engine turns even with exhaust stroke the plugs will fire
Just for S*** and giggles take your CAS off turn it 180 Degrees from where it is siting on rear intake camshaft
It’s a ’93 which has no CAS unit to get 180 degrees out, it has crank and cam sensor behind timing belt. And the wasted spark firing at top of exhaust stroke shouldn’t have any gas to cause backfires into turbos, just like it doesn’t on a normal running engine.
 

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Maybe someone in this group would have new ideas?
The pictures of cam gears and crank gear would have been more useful if they where taken with crank and cam gears on they’re timing marks, all I could see there was none on timing marks in pictures. Wondering if you used correct marks?:unsure:

Also you assuming the ECU is OK because you didn’t see any signs of capacitor leakage, is well….. Simply that an ASSUMPTION, they can and have failed without any visual signs. If you can post clear picture of circuit board, I’m sure someone here can at minimum identify if they are originals, which if so it’s a strong possibility of them being your problem.

If mechanical timing (crank/cams) correct, no ECU problem, no bent valves, about the only other thing that might could cause backfire thru intake valves would be the cam sensor not being in correct alignment with crank sensor, causing spark to fire on cylinders when intake valve is still open.
 

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Discussion Starter · #13 ·
The pictures of cam gears and crank gear would have been more useful if they where taken with crank and cam gears on they’re timing marks, all I could see there was none on timing marks in pictures. Wondering if you used correct marks?:unsure:

Also you assuming the ECU is OK because you didn’t see any signs of capacitor leakage, is well….. Simply that an ASSUMPTION, they can and have failed without any visual signs. If you can post clear picture of circuit board, I’m sure someone here can at minimum identify if they are originals, which if so it’s a strong possibility of them being your problem.

If mechanical timing (crank/cams) correct, no ECU problem, no bent valves, about the only other thing that might could cause backfire thru intake valves would be the cam sensor not being in correct alignment with crank sensor, causing spark to fire on cylinders when intake valve is still open.
Hi,

thank you all for the responses. I will turn the engine by hand to TDC according to the marks and make more fotos for diagnosis. Also I willl take apart the ECU from its casing and make some photos of that aswell. I also got some kind of software that can access the live data per OBDI for the Stealth on my laptop, I tried and looked into it once but had no idea what was going on. I´ll try and make some recordings/photos of it too.

I´ll be back
 

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Discussion Starter · #14 ·
Hey hey.

It took again some time for me to get around, make the photos and video of the car and getting to posting it on here. I´ve tried to capture as much information. I thank you all for trying to help me with this situation.

I hooked up a OBD software I got for the 3000GT. Im really a noob at this software stuff, so I don´t really know where the values should be, and whats-what.

Youtube Video, OBD software

I also made photos of the timing marks and how the timing belt is aligned.
 

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Discussion Starter · #16 ·
And here I´ve made some photos of some of the electronics..
 

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The spliced wiring by hood release ??

MFi relay cut wire with but connector ??

I Did see some irregularity in one of your caps...
Has a bulge off to the side of it
Questionable??



Your timing is dead on (timing belt)
 

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The spliced wiring by hood release ??

MFi relay cut wire with but connector ??

I Did see some irregularity in one of your caps...
Has a bulge off to the side of it
Questionable??
👆👆👆 I agree and good eye on bulged capacitor as I didn’t notice that, but I did notice they are original from ’93 which is bad and need replacing at a minimum.
 
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