Engine Swap Complete but a few problems

85TbirdSC

Registered User
I just bought a 91 SC 5 speed. The engine in it was knocking due to a hole in the oil pan from bad mounts. I already had an 85 Tbird that I had put a 89 or 90 SC Engine in back in 97. The 85 has been sitting for about 5 years. I started the engine in the 85 before I pulled it out and it ran fine. Power Steering pump was locked up and the the car had no brakes so all I could was start it. I also ran a compression check and it showed 150-155 on all six.

Just completed pulling both engines and installing the engine out of the 85 body into the 91. I pulled the engine down to the long block before installing it. Replaced all gaskets except the heads. Put on new engine mounts, oil, oil filter, air filter, fuel filter. Started it up last night and drove it to work Today. It runs strong and Idles fine. Here are the issues I have found so far.

1. Oil pressure gage reads 0. I know it has good oil pressure. I figure the sesor I used in the 85 must be different than the 91. I can't remember changing it before but it showed good pressure when I started it up the other day in the 85 body.

2. ABS light comes on for a second when I hit the brakes. I know the car needs front pads and prob rotors also. Will this cause the ABS light to flash? Or is there anoother problem. I can hear the ABS motor run for a couple of seconds when I turn on the key or push the brake pedal.

3. Trans growles when shifting into 3rd gear. Not real loud but a pretty good noise. I replaced the clutch, Pressure plate, release bearing, slave cylinder, pilot bearing, and had the fly wheel surfaced while the engine was out. Prob did/will not make any difference. I am going to try changing fluid and putting friction modifier in the trans. Any other Ideas or should I get ready to drop the tranny for a third gear syncro?

4. Cooling fan. I have let the engine Idle for a good while(till it is in the upper end of normal on the guage) and I have have not seen the fan running. I drove the car about 50 miles this morning and it never got adove 1/2 way on the guage. Not a lot of sitting in traffic but a little. When should the fan be comming on. We just had a cold front hit last night. It is prob in the 50's Today. Other than letting it run till the fan comes on or it over heats how do I check it?

5.The check engine light is/has not came on since I started the engine but is does come on when KOEO. The check guages light is on. The fuel guage does not work. Shows Empty all time. That and/or oil pressure is prob why?

Thanks for any help

Sean
 
Hello.

First, about the oil sensor. I am also having this problem intermittently after the car warms; and in your case I would say either the sensor is wrong, bad, or both. They can be a cheap part to replace, worth a try.

Next, the ABS light. There could be several things which cause this light, including a simple lack of fluid in the resevoir. One thing on the earlier SCs with TEVES MARK II that seems to occur is a bad accumulator. This usually results in alternating brake & abs lights, a loss in fluid, and extra pump cycling.

For the standard trans; only thing I can think of which would cause a noise unique to third gear is synchros. These are shared between 1&2, 3&4.. so look for 4th also. The 1-2 is usually first to go. Can you describe the noise in greater detail? Is it a gear-grinding noise or a low pitched low frequency sound?

Cooling fan: These sometimes do not turn on until the end of M in norm. The earlier cars had 1 fan with 2 windings.. High and low. It is possible for one winding (usually low) to burn out and the other to function. At any time, if you turn on the A/C the fan should activate. If it does, but the fan still doesn't cycle with the car, the problem may lie with your ECT sensor near the intake, infront of the SC. If low doesn't turn on at the right time (220), high should activate shortly afterwards (227). You can also unplug the ECT to activate the high speed fan.

Your check gauges light is activated by an out-of-range reading of any 3 gauges.. oil pressure, temperature, or fuel. In this case, probably both your fuel and oil gauges.

Lastly, just an inquiry, I noticed you did not replace the head gaskets. These are susceptible to corrosion & apparently often look bad by the time the motor nears 100k. You probably are aware of the condition, but incase you were not I thought I would mention it.
 
Just a thought....

Since neither your oil pressure gauge or fan are working, check to see if you've switched the sensor wires.
 
Good idea. I believe the red connector goes onto the lower oil pressure sensor, and the gray onto the coolant sensor. Confirmation anyone?
 
Problems

1. Oil pressure sensor is most likely the prob. I talked to a buddy that helped with the SC engine swap into the 85 body and he is pretty sure we canged the send unit. He says he remembers pulling one from an SC at a wrecking yard when we where gathering parts. I will change it out this weekend and see.

2.ABS Light still the same but I have noticed that the key sometimes does not go all the way to the run position when released from start. Happened to me twice today and how I noticed was stepping on the brake and getting the feeling of a a car with power brakes and the engine off. When that happened I also noticed that some of the accessories did not have power. Like the climate control read out, radio etc. I could wiggle the key and evertyhing would power up and braked would be normal again. ABS light comes on for a sec when you first hit the pedal.

3. Trans does not seem to be getting any better or worse. It is a pronounced gear gringing noise but only into 3rd gear and only during the shift. Once in third it seems fine. Makes no noise at all into any other gear, Go figure.

4. Cooling fan seems to not be a problem. I have caught it running a couple of times and no overheat problems so I think it is ok. I have put about 125 miles on it since last night and you can see the temp climb a little in traffic and then fall when the fan kicks on. Rises again after a cpl minutes and falls again when the fan kickes on. Seems to be ok. Also temp/oil gauge wires are prob in ok since the temp guage seems to follow the fan. And red is to the oil sender gray to the temp.

5. Check guages light is still on. As before. Fuel/Oil press will need to be fixed before this prob will go away. The check engine light did come on tonight. I took my wife for a spin after I got home from work and after a few minutes I pulled over and ler her drive. Less than a mile later the check Eng light came on. I had her pull over and I looked under the hood. Nothing obvious wrong. I had her turn the engine off and back on. No more ck eng light. Drove 10-15 more miles and no light. Go figure women drivers I suppose.

Thanks for the replies and I will keep posting on the progress that I make.

Sean
 
Digitalchaos(Head gaskets)

Digital

Yes I have heard about the head gasket probs with these engines. I did not change mine because that was the break piont for me. I already had a good engine(less than 30k on it) and if I puled the heads than I would have also changed rings, mains, inserts, oil pump etc....etc.

I still have the complete engine that came out and I am going to rebuild it but not stock. I am not exactly sure what I am going to do but at a min port and polish intake heads and exhaust, Little more cam, After market exhaust system, overdrive pully, bigger injectors, throttle body, etc....

It will take me awhile to get the time and funds to do all of this and I did not want the car sitting while I was building the engine so I did the swap and wanted to seal the engine up as best as possible w/o puling the heads, buying head bolts etc. It may be a couple of years before I finish the other engine so I want it to be dependable untill then. It will not be a daily driver at any rate, just something to play around with. Plus I had to sell the wife on the fact that I already a good a engine so I could buy the car in the first place. How would that look if I overhauled it before I put it in.

Sean
 
ABS Light

Well did front brakes and new front rotors. ADS Light still comes on for just a second when I hit the brakes. When I hit them hard it stays on longer. The red Brake light only comes on when the parking brake is set.

I searched through ABS problems and everyone else seems to have both lights.

Any Ideas anyone.

Sean
 
fluid levels? My red one comes on when my fluid is too low, I know that sounds stupid to an obvious expert like you, but just thought I'd try to help heh =p
 
I agree.

The red "BRAKE" light coming on momentarily when you first hit the brake pedal has been the fluid level low on my SC's. It's best to check it with the car level, so you can be sure the level is right on the line.

Of course cleaning the outside of the resevoir helps too. :p

Lee
 
Just a thought-- My ABS light coming on for a brief second ended up being my brake light switch. Either out of adjustment or bad. The car feels braking before it actually sees the electronic confirmation, applying the ABS. An easy way of checking it is get to speed, apply cruise, and tap brake lightly-does cruise turn off? If not, this could be your prob. Or just see if the brake lights come on w/ slight pressure on pedal. Good luck.
 
Update

1. ABS Light: Brake light switch seems to be working corectly so it still comes on for a sec when I hit the brakes. Brakes seem to work great. Red brake light is not comming on so I am not sure if I need an accumulater or not?

2. After I replaced the fron pads and rotors I had the state inspection done. Passed with flying colors on emisions and everthing else.

3. I am going to do the oil press guage mod listed in the Literature section to hopefully fix the guage preblem. I already have the sending unit from the pressure type guage installed so it should be a pretty easy mod.

4. The odometer/trip odometer quit working. Speedo still seems to work fine but the trip/odometer is not working. When I have the guage cluster out for the oil pressure I will look into it. Probably not much that can be done for it.

5. Boost Pressure: What should it read when. It reads about 19-21 InHg at Idle. Hardly ever reads more than 10psi boost. If I really get on the throttle in 2nd of 3rd gear it will read 12-13psi but that is as high as it the only way it will get that high. Is this normal, low, high? When this engine was in the 85 body I never had a boost gauge so I do not have any thing to compare it to.


Thanks for all the help,
Sean
 
For boost: 12 psi is the max on a stock motor

I have been having the same thing with my brakes just both abs and the red brake light come on. The one question that I have for you is about the abs cycling when you apply the brake. Does the pedal seem very hard right as you first apply the brake and then soften a second later? I.e. going 60mph you apply the brake fairly swiftly does it seem like there is a lot of resistance in the pedal and not much stopping, then a split second later the pedal softens and then the car slows down swiftly. If so, I think your problem is the accumulator
 
Brakes

No the brakes seem fine at all speeds and under all conditions. The pedal seems normal. Not overly hard or soft. Stops great.
 
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