View Full Version : Swapped frames and now it won't freaking run!!!!
DrGonzo
11-01-2010, 08:22 PM
Ok so if anyone has been following my other thread : http://www.3sgto.org/showthread.php?304-Saved-From-The-Crusher-93-Stealth-TT-Rebuild-Restore
You will understand what I mean by swapped frames!
The engine was originally from my 92 FWD TT. I have since then swapped it into an AWD TT frame. The engine ran fine "minus a tune" the day I pulled it from the FWD frame. Nothing on the engine was touched beside what needed to be removed to pull it out. Even the engine wiring harness was swapped over to the new frame.
The problem I am running into is that the car will crank over but not fire! I am seeing an issue when cranking it, I get a thud and all lights dim down "Think the starter is on its way out" happens every now and then! Timing is fine so it's not the pistons hitting anything. I hooked up my logger today and I am getting TDC and Injector circuit codes. WTF!!! The engine ran fine before transplanting it! So I tried messing with the cam/crank sensor and still nothing.
I need to check spark and fuel. Got dark to fast on me!
So here are my questions? Bare with me as I am still new to tuning....:D
1. I zero'd out all fuel adjustments on my SAFC 2 for low and high would this have anything to do with the problem?
2. The cam sensor can only go in one way. The tab thing has a notch for top but there is no corresponding mark on the cam? so how the hell do you know which way is which??? I am not about to go back and forth turning it. I need to get it set so I can look into other issues.
3. When logging with MMCD I noticed that my timing slot is a - and then goes to 4degrees every coupe of seconds then back to -. When I adjust the Cam sensor the timing doesn't move on the logger. Should it?? If I remember right it should but it has been a while since I have had to break out the logger.
4. All starters are the same for FWD vs AWD correct?? Do you need to shim the starter on the AWD trans?? Am I wrong thinking the thud issue is a bad starter or is it something else?? It is almost like the starter locks for a second then gets going again!!!
I'm looking at the log files and there must be a bad connection somwhere as my timing graph is like a dotted line:
- ------- - - - - - - --------------- - - - - - - - - ------------ - - - - - -
Any help would be appreciated..........
Unknownvr4
11-01-2010, 08:32 PM
Check your motor to frame ground
DrGonzo
11-01-2010, 08:41 PM
Yeah I need to check into that. I am in the process of doing a battery relocate so I don't really have any grounds in the engine. The battery ground it going to the strut tower bolt. I figured with solid mounts it would be good to transfer the grounding to the engine.
Anyone know what best points to ground are. I had a diagram showing them using a Big-Tyler kit but I'll be damned if I can find it when I need it.
I'll start with the grounding tomorrow. Any other ideas???
Unknownvr4
11-01-2010, 08:48 PM
Thats why its not starting. You need to ground the motor to the frame. Its usually done from the intake plenum to the firewall
Chris@Rvengeperformance
11-01-2010, 08:50 PM
awd vs fwd starters are not the same
stealthee
11-01-2010, 09:06 PM
awd vs fwd starters are not the same
I used to think the same thing. Other have used the same starter when swapping to an AWD trans on their FWD car.
n2nsanity
11-01-2010, 09:10 PM
i've never messed with the cam angle sensor, but i would think it should still start no matter where it is set, and especially if its somewhere near the middle.
do 91's and 92's have a crank sensor? i didn't think they did.
the grounds could possibly be an issue, but following your other thread, it doesn't look like you missed anything.
not sure what all parts of the harness and/or electronics you switched out or left on the new shell, but the mfi relay is different over different years and probably also between n/a's and tt's. i have 2 or 3 of them laying around and i think they were all different part #s.
the only electrical things i can think of that could cause a no start issue would be fuel pump, mfi relay, ptu, coilpacks, bad grounds ground, cam sensor
you're way better at this than me, but it's always easy to overlook the little things.
good luck with it
Chris@Rvengeperformance
11-01-2010, 09:16 PM
I used to think the same thing. Other have used the same starter when swapping to an AWD trans on their FWD car.
may work, but can't be ideal for tooth contact.
stealthee
11-01-2010, 09:18 PM
may work, but can't be ideal for tooth contact.
Its the same. The starter mounts differently due to different bellhousings to make up for the flywheel size. Trust me, like I said I thought the same thing as you before, but was corrected and informed that MTX FWD starters are the same as AWD starters.
DrGonzo
11-01-2010, 09:30 PM
Yeah I need to look into the ground issue and at least get a good ground going to the upper plenum. As for the starter I have only heard they are the same from research but not definitive on the answer.
Fuel is fine as the fuel pump is hotwired. MFI is good to go. The harness connecting the MFI relay is part of the engine wiring harness that was swapped over form the other car. Al electronics were swapped over also. TT Fuel relay and resister are out of the picture since the pump is hotwired.
91/92 used the CAS which is basically the crank/cam angle sensor built into one unit on the rear head. It is adjustable for setting the timing.
Lithium
11-01-2010, 10:45 PM
does the check engine light turn on?
Greg E
11-02-2010, 01:07 AM
The only time ive ever seen injector codes is when the ecu goes.
Unknownvr4
11-02-2010, 02:14 AM
... I hooked up my logger today and I am getting TDC and Injector circuit codes. ...
Wait a second. Im getting injector and crank/cam angle sensor codes on my car. It still runs but tries to die/restart/die/restart and then acts normal after a while. Maybe my ecu is going out..
After the ground issue, try swapping out the computer for a known good one in the area and post up results.
DrGonzo
11-02-2010, 06:31 AM
Computer is fine! It has already been rebuilt.
If there is anything wrong with the ignition/timing you can get the TDC, Injector, Ignition circuit, Etc... It's just how the ecu interprets what is going on. if the CAS sensor is not readin correctly it will throw codes for all thre as those are the things not working due to the CAS.
CoreyB
11-02-2010, 03:13 PM
The thud and lock sounds like its firing out of time.
Mikes2nd
11-03-2010, 08:20 PM
timng should be showing... hmmm
DrGonzo
11-06-2010, 06:59 PM
Well I did some digging today and found that the CAS was not getting the 5v from the ECU. So I took a look at the ECU and noticed the small top plug was not plugged in all of the way....Dooohhh! It must have made it's way loose when I was running the wiring for the AEM wideband.
So now I am not getting any codes but the car still will not fire over. Checked the plugs and I am getting fuel as the plugs were coated in fuel due to the CAS issue as the ECU limps into all open injectors for 4 seconds if it does not get a signal. So the engine is flooded right now. Hooked up my timing light just to see if I am getting voltage to the plugs. Light fires every time......
My question now is will a timing light fire if the plugs are fouled??? It just looks for a signal correct, which means my plugs could be fouled due to cylinders being flooded!
I'm going to let the car sit for the night and try to start it again tomorrow. Should give the plugs enough time to dry out.
stealthee
11-06-2010, 07:07 PM
The wires fire no matter what the plugs are doing.
DrGonzo
11-06-2010, 07:33 PM
Thanks....
So I'm thinking that with the amount of fuel in the cylinders it just wet fouled the plugs causing the no spark. I'll crank it over tomorrow and hopefully it will fire right up!
DrGonzo
11-08-2010, 08:22 AM
OK... So the plugs were all fouled so I went and changed them out. I tested them out and I am indeed getting spark now. I am also getting Fuel but still the car will not fire! So I check the compression and it's 180 "Engine still have 10:1 n/a pistons" so it's not a compression issue.
So I'm thinking it has something to do with the CAS "engine is 1st gen". I pop it off and rotate it 180. Now when I go to start the car it tries to fire for the first couple turns and then nothing. It also sounds like it firing on the exhaust side. OK So the CAS is off. I turn it back 180 and try to start and nothing....... WTFH!!!!
So does anyone know an absolute method to find out which way the CAS is supposed to be mounted?
The manual is worthless and doesn't stat anything. Stealth316.com just states to make sure you reinstall it the same way it came off. But I cannot find how to install it to make sure it is in correct. I need to eliminate the CAS form being an issue and until I can get the damn thing mounted correctly I am going to be wondering if it is in there right or not!!
If I leave the CAS in the center adjustment position the car should still start and run until I can set the timing correct?
I am also not getting any CEL's now which makes it even more of a pain to figure out.
Greg E
11-08-2010, 09:33 PM
It should show signs of life if you center the sensor. That sensor tells the ECU when to fire the plugs and when to pulse the injectors. If it's off by even a few degrees, nothing happens when it should.
Mikes2nd
11-08-2010, 11:38 PM
do you have the electrical manual? it tells you how to troubleshoot the crank angle sensor... if you have fuel/spark... it can only be the signal now.
Do you have a spare cas sensor?
I picked up a bunch when people were selling them for like 25$
triple check your timing with the gears and cams... cam angle sensor...
i've never messed with the cam angle sensor, but i would think it should still start no matter where it is set, and especially if its somewhere near the middle.
do 91's and 92's have a crank sensor? i didn't think they did.
the grounds could possibly be an issue, but following your other thread, it doesn't look like you missed anything.
not sure what all parts of the harness and/or electronics you switched out or left on the new shell, but the mfi relay is different over different years and probably also between n/a's and tt's. i have 2 or 3 of them laying around and i think they were all different part #s.
the only electrical things i can think of that could cause a no start issue would be fuel pump, mfi relay, ptu, coilpacks, bad grounds ground, cam sensor
you're way better at this than me, but it's always easy to overlook the little things.
good luck with it
i haven't read everyone's comments but off the first page i see no one said anything but yes the 91 92's have crank sensor, they are included in the CAS, it's one whole unit.
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