87 TC trouble shooting

Topic: 87 TC trouble shooting (Read 1858 times) previous topic - next topic

87 TC trouble shooting

December 10, 2011, 03:02:14 AM

first, let me state that i DON'T have a CEL on and yes the bulb is good.. the motor is mostly bone stock with a gillis valve and cone filter

i popped my follower back on this morning and fired her up, purrs like a kitten. she developed a very slight miss that goes away with the tiniest little tap on the throttle, so i figure it might be the fact that she's running old plugs or it's probably the TPS needing a little adjustment.. changed the cap, rotor and wires, since i had brand new parts left in the trunk by the previous owners.

now, she idles around 1000-1100rpms, sometimes it'll come down to 900. at 10-1100, the boost gauge is reading 14-15in/hg, is that fairly normal?

NOW.. when i rev it to about 25-3000rpms, the needle on the boost gauge doesn't go above zero, BUT i know i'm getting boost because i eased out on the clutch at 1/4 throttle and she left 2 tire marks down my (gravel) driveway and she scoots along better than a stock 5.0 rustang.. possibly a faulty gauge or a vacuum leak?

and which way do i turn the gillis valve to raise the boost, in or out? i've never had 1 like this but i think mine may have taken a and got stuck, because i feel no difference when i turn it all the way in or all the way out (or anywhere inbetween)

and how do i get the factory boost gauge to work, hook the boost solenoid back up? i figure that may be a good way to test and see if my boost gauge took a

at first i thought the turbo was seized, but i popped the elbow off the front of the compressor housing and she spins freely, with zero shaft play

87 TC trouble shooting

Reply #1 – December 10, 2011, 11:56:40 AM

Virtually any manual trans car can turn the tires on gravel. No, the car won't show any boost on the gauge when running up the rpm's in neutral with no real load on the motor. Take it out on the road and put the engine under load and see if it builds boost.
As for the wandering idle, clean the IAC valve and see if it settles down. The factory boost gauge isn't all that accurate anyway, so if it were me, I'd leave it disconnected anyway.

87 TC trouble shooting

Reply #2 – December 10, 2011, 12:03:33 PM

I would run codes anyway even if you don't have a CEL. Like Jangus said, you won't see boost just revving it in neutral. On the Gillis valve, you turn it in (tighten) for more boost and loosen for less. The factory boost gauge is mechanical, just a vacuum line running to the back of the cluster. Mine comes from the vacuum tree and has a red stripe on it (I think.) If you don't see boost after driving it on the road you may want to investigate the wastegate actuator.

87 TC trouble shooting

Reply #3 – December 10, 2011, 12:10:27 PM

Quote from: jangus;375155

Virtually any manual trans car can turn the tires on gravel.

i know that, but not at 1/4 throttle and very slowly letting off the clutch.. the driveway is also hard packed back there, not loose gravel

as for the boost gauge, it's not showing anything under load, either

the idle doesn't really wander, surge or anything like that.. it's all just according to the temp, typical really, but 900 is her minimum idle at full temp, so i have to bring it down just a tad

my biggest issue right now is the gillis valve and boost gauge (or at least the reading it's giving me).. the highest i got out of the gauge was 3psi, but i know the car is pushing a lot more than that.. i just wanted to hook up the stock gauge to see if my Phantom took a on me

87 TC trouble shooting

Reply #4 – December 10, 2011, 12:15:53 PM

Quote from: Loaded87IROC;375156

I would run codes anyway even if you don't have a CEL. Like Jangus said, you won't see boost just revving it in neutral. On the Gillis valve, you turn it in (tighten) for more boost and loosen for less. The factory boost gauge is mechanical, just a vacuum line running to the back of the cluster. Mine comes from the vacuum tree and has a red stripe on it (I think.) If you don't see boost after driving it on the road you may want to investigate the wastegate actuator.

ran for CEL codes anyway (i know sometimes they don't trigger the light), i didn't get anything

thanks, i'll turn it back in and see what happens, but i think it's stuck from sitting

wastegate actuator, got it.. i'll check it out now.. first going to try finding the factory boost gauge's vacuum line, i don't think it's hook up.. going to pull the line running to my phantom gauge and make sure it's alright, then re-install it

87 TC trouble shooting

Reply #5 – December 10, 2011, 12:29:24 PM

The valve is simple enough to take apart and clean if you think that may be the issue.
http://www.boostvalve.com/faq.html

87 TC trouble shooting

Reply #6 – December 10, 2011, 12:54:28 PM

Quote from: Shadow;375157

the idle doesn't really wander, surge or anything like that.. it's all just according to the temp, typical really, but 900 is her minimum idle at full temp, so i have to bring it down just a tad

It is suppose to idle right around 1,000 rpms. Here is tech article on adjusting idle.

http://www.turbotbird.com/techinfo/Idle-TPSadjustment_Revised_June2005.html

87 TC trouble shooting

Reply #7 – December 10, 2011, 12:55:04 PM

LOL i just cleaned it, it was definitely stuck.. i put it back together and 19psi later, bye bye follower.. so now i have to fix that, AGAIN, or leave it until i get to the junkyard for a RR.. the idle miss is also gone, well.. was gone until the follower jumped off again lol.. i turned it down to where it's running about 900rpms cold, 700-750rpms warm