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jre97
01-23-2004, 04:24 AM
The engine and/or tranny has a vibration in my 89 xr7. I don't know much about the car's history other than it has a remanufactured engine that was installed about 1000 miles before I bought it. I got the car for $400 and it wasn't running. I put on a new ignition module, coil pack, and spark plugs. That got it running but not well. I found out that one of the injectors wasn't spraying well, took them off and cleaned them and now it seems fine.
Any way it has a vibration with the car running in park or neutral (not moving). It seems to come to a head about 2000rpm and then gradually smooths out. The car is firing on all six cylinders and they all six are showing about 150psi of compression. I removed the tranny to replace a leaking rear main seal and didn't notice any cracks in the flex plate/flywheel but I did notice something strange, the bolt head pattern of the fly wheel bolts is stamped on the torque converter like the ar hitting or have hit in the past. Now with less than 50 miles on that rear main seal and it is leaking again. It almost acts like it has the wrong flywheel or a bad torque converter or maybe a bad harmonic balancer. Any Ideas what could be causing this?

MIKE 38sc
01-23-2004, 04:00 PM
Ah yes....Those bolt heads imprinted in your torque converter means that the converter is ballooned.(I have one just like it)
When the converter balloons some internal parts fall out of place and drop down in the converter. A ballooned converter means the converter has been spun too fast by the engine.
The stock converter starts to balloon at just about 6,000 RPM.

trife86
01-23-2004, 04:02 PM
"I don't know much about the car's history other than it has a remanufactured engine that was installed about 1000 miles before I bought it. I got the car for $400"

no one would do that than sell it 1000miles later for $400

got to be a big proble you dont know about.... these cars dont sell for cheap

MIKE 38sc
01-23-2004, 04:19 PM
Possable scenario:
Someone hotroded original engine pretty bad(evidenced by balloned converter) and they eventually blew the engine. After installing the remanufactured engine the vibration was noticed and the frustrated owner said the hell with it and dumped it just to get rid of it. Happens all the time with most cars, thats how I got mine so cheap.

jre97
01-23-2004, 05:20 PM
Exactly, the boy told me that he blew up the old engine on the interstate racing someone. He just raved about how fast it was. He was about 16 or 17 years old and he had it at my brother-in-laws garage to get it running and I guess he didn't have the money for a coil and an ignition module. Which is what my brother-in-law told me was wrong with it and that got it running. I was concerned about that vibration though thanks for your help.

Ripper
01-23-2004, 05:29 PM
Thanks for asking this question!

Mine is doing the exact same thing. the motor runs well and strong but vibrates without a miss and idle and just above to about 2k like the original posters.

before I thought for sure it was the motor mounts, but when I checked em they seem okay (and from the bottom they look like the solid mounts already) the oil pan is above the cross member so I think they are okay.

is this ever associated with noise?? the tranny is bad and only shifts 1-2 but does it well, the motor is real strong but there is a hint of metal to metal along with the vibration

I got a new tranny and it came with converter so I was thinking this would take care of it anyway.

jre97
01-23-2004, 05:50 PM
Originally posted by Ripper
Thanks for asking this question!

Mine is doing the exact same thing. the motor runs well and strong but vibrates without a miss and idle and just above to about 2k like the original posters.

before I thought for sure it was the motor mounts, but when I checked em they seem okay (and from the bottom they look like the solid mounts already) the oil pan is above the cross member so I think they are okay.

is this ever associated with noise?? the tranny is bad and only shifts 1-2 but does it well, the motor is real strong but there is a hint of metal to metal along with the vibration

I got a new tranny and it came with converter so I was thinking this would take care of it anyway.
The metal to metal sound could be a busted flex plate! I just found out that autozone sells stock torque converters for $80.

MIKE 38sc
01-24-2004, 03:09 AM
Make sure its an SC converter. The way to tell is look at the center of the converter. There should be a swirl pattern of dimples in the converter housing spreading outward from the inside. If it does'nt have that swirl pattern its not the right one.

jre97
01-24-2004, 08:28 AM
Originally posted by MIKE 38sc
Make sure its an SC converter. The way to tell is look at the center of the converter. There should be a swirl pattern of dimples in the converter housing spreading outward from the inside. If it does'nt have that swirl pattern its not the right one.
On the front or back? Because I don't recall seeing any dimples on the engine side.

hockeydad2
01-24-2004, 09:27 PM
to all the above posts. does the engine shake at idle like a bad vaccum leak? about six months ago i bought a 90 sc that the owner said was over heating. he had replaced the water pump and then gave up. i had the car towed home thinking headgaskets even if no coolant in the oil or no white smoke out the back. i tried starting it and it ran like crap. found a broken vane on the crankshaft damper. replaced the damper (used one), and crankshaft sensor. got it running, still felt the "vibration" around 1500 - 2000 in park or netural. did a compression check, all cylinders 145 -150 psi. replaced plugs and checked for vacuum leaks and error codes, no error codes, all pass. since replaced plugs wires, swapped dis module with known good one, still getting the vibration. NOTE: passed california smog easily and i have driven the car about 70 miles with no overheating. the vibration or engine shaking at idle even broke the head pipe hanger (rod) where it goes into the transmount. any suggestions??

hockeydad2
01-24-2004, 09:39 PM
additional comments for previous post, replaced motor mounts (solid) and swapped known good iac valve.

MIKE 38sc
01-24-2004, 11:51 PM
Heres a pic of the dimpled swirl pattern I was talking about. I highlighted some of the dimples with black marker incase you cant see them.

MIKE 38sc
01-24-2004, 11:56 PM
Heres a shot showing the ballooning, notice the bolt heads imprinted on the converter housing thats the proof.

Ripper
01-25-2004, 12:41 AM
thanks for your post mike38sc.

I recently bought a tranny with a rebuilt torque converter and it looks just like your pic except its all black and says "biltron" "AOD" and a date in 1999.

Ever hear of biltron? there are also markings on the tranny making me think it was rebuilt aswell.

92silverlx
01-25-2004, 01:13 AM
ok, I'm having a similar problem with a recently purchased 92 SC the car ran fine and still does however i am also experienceing what feels like "engine vibration" but not in PARK or in NUETRAL it occurs in either REVERSE or DRIVE but only when i come to a complete stop it actually feels like it starts to die, when i brake suddenly when coming to a stop so it happens at low rpms, so far i've replaced wires, plugs, thermostat, temp sensor, upper and lower rad hoses, and oil/filter to no avail....the car is all original from original owner 116k miles, aod, the car had a problem running a little to hot but never overheated but now runs substantially cooler right around normal....any and all help is greatly appreciated


Thanx Joe

MIKE 38sc
01-25-2004, 02:45 AM
Originally posted by Ripper
thanks for your post mike38sc.

I recently bought a tranny with a rebuilt torque converter and it looks just like your pic except its all black and says "biltron" "AOD" and a date in 1999.

Ever hear of biltron? there are also markings on the tranny making me think it was rebuilt aswell.

Yeah...I've heard of Biltron. www.biltronauto.com You can find the info on your converter there.
The swirled dimple pattern converter is a std 5.0 converter and its used in the SC. The NA 3.8 AOD uses a different converter that does not have the swirl pattern.

hockeydad2
01-25-2004, 05:07 AM
thanks for the pictures mike38sc. Ripper does your engine shake much at idle? mine also runs fine and idles fine (no missing) but the engine seems to shake too much at idle.

Ripper
01-25-2004, 07:57 AM
Pretty much just at idle. I was kinda thinking it was motor mounts, I have to admit it kinda felt and sounded like the motor was resting a little bit on the cross member from the feel and sound of the rattle.

Looking at it the motor mounts seem fine and I am about to change the tranny and converter since they are bad anyway, will see what happens then.

Part of the noise I heard was coming from my SC, sounds like a bad bearing knocking around

Thanks for the link mike!

jre97
01-25-2004, 08:18 AM
Thats exactly what my torque converter looked like as far as the bolt pattern any way. Don't most all aod and a4ld torque converters have that same "dimple" pattern though. I replaced one in my moms bronco2 (2.9l A4LD) last summer for her and it looked like that on the back side. I've also seen a couple out of some mustangs that looked like that.
[edit]Oh I guess I didn't read far enough. Sorry[edit]

hockeydad2
01-26-2004, 03:46 PM
Ripper, Jre97,
Sounds like Mike38sc put us on the right track with the torque converter. yesterday i picked up a sc 5 speed trans, and the guy i bought it from has the same problem with a 350 camero, engine shaking at idle, no error codes and passed calif. smog, and a vibratrion felt from idle to about 2000rpm. he replaced the converter and that fixed it. THANKS Mike38sc, i had giving up on my 90 sc project car, now i hope to have the trans and converter replaced this weekend if the weather is good.

Ripper
01-26-2004, 03:52 PM
I was reading some of mike38sc 's oldr post about the tranny and they were awesome!

jre97
01-26-2004, 06:10 PM
you guys rock!