just finshed my swap, now i have a couple problems.......

[Highnitro]

hey,

i just swapped an 89 7mgte (which only has 150 miles on a complete rebuild) into an 88 turbo shell. im using the 89 ecu and auto harness. i finally finished hooking everything up and now im having a couple problems. first off it has some white smoke coming out of the exhuast, im pretty sure its not a bhg because i just put a titan 1.5mm gasket, and arp head studs in it. im thinking that my turbo might be going out. is that a possibility? also before i put the engine in this shell it ran great in my 89, now thats its in the 88 its stumbling really bad when you rev it up, and its not running smooth at all. what could cause this? im going to check for codes tomorrow if i can figure out how to do it. any help or ideas will be appriciated.

Thanks,
Matt

 

[mkiiSupraMan18]

My guess would be going from 89 to 88, there are some sensors that are different making it run like crapp.

maybe a boost leak? Plug wires off/in incorrect order?

 

[gtsfirefighter]

hey,

i just swapped an 89 7mgte (which only has 150 miles on a complete rebuild) into an 88 turbo shell. im using the 89 ecu and auto harness. i finally finished hooking everything up and now im having a couple problems. first off it has some white smoke coming out of the exhuast, im pretty sure its not a bhg because i just put a titan 1.5mm gasket, and arp head studs in it. im thinking that my turbo might be going out. is that a possibility? also before i put the engine in this shell it ran great in my 89, now thats its in the 88 its stumbling really bad when you rev it up, and its not running smooth at all. what could cause this? im going to check for codes tomorrow if i can figure out how to do it. any help or ideas will be appriciated.

Thanks,
Matt

How much white smoke? Any shaft play in the turbo? Are you using the same IC piping and IC that was in your 89? Same exhaust?
Give us details on your setup then and now.

My guess would be going from 89 to 88, there are some sensors that are different making it run like crapp.

maybe a boost leak? Plug wires off/in incorrect order?

I wouldn't think the sensors would be an issue since he is using all 89 setup, ECU, wiring harness.

Is this an early 89? Were you able to plug in everything under the dash?

 

[Highnitro]

its not alot of white smoke, but i havnt driven it, its just been at idle and 3000 rpm. there is shaft play in the turbo, thats why im thinkin it could be going out. there are a couple connectors that didnt hook up in the glovebox, but im gunna get the electronics out of the 89 so everything will hook up. its the same setup that was in the 89 except i added a walbro 255 and an aeromotive afpr. its set at about 43 psi.

 

[jdub]

43 psi is high, especially if you're using stock 440 injectors. Drop it to ~30 psi with the vac line attached.

I hope you decked the head AND block for a MHG (50 RA or less for the Titan)...ARP stud torque should be 80 ft/lbs using moly for lube.

 

[mkiiSupraMan18]

I wouldn't think the sensors would be an issue since he is using all 89 setup, ECU, wiring harness.

Is this an early 89? Were you able to plug in everything under the dash?

^ That's what I was meaning, and him saying some connections weren't hooked up...

 

[Highnitro]

yes i did deck the head and block with the tms headgasket. also the arp's are at 80 ft/lbs. i just took the car for a spin and it stopped smoking and now seems to be running fine, my only problem is that the headlights arnt working. they did at first, and now they just stopped. all the rest of the lights work.

 

[mkiiSupraMan18]

be honest.... was it something stupid you forgot...?

We've all done it. :icon_bigg


Glad to hear though.

 

[jdub]

You may have had some residual coolant in some of the cylinders. I would drop the fuel pressure though...FP that high can cause a rich miss at high RPM.

I would change the oil NOW. If you have coolant in your old oil, it will kill the bearings pretty fast...rod knock is a follow-on to a BHG exactly for this reason. Do a change with a cheap oil like WalMart SuperTech 5W-30 and filter, run it for 50 miles, then change again to a quality 0W or 5W-30 oil and Wix or NAPA Gold filter.