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"Christine" does not like me

1718 Views 24 Replies 6 Participants Last post by  scooter111
1983 Seville, 4.1
I posted last month about an issue with her almost stalling and having to "bounce" on the gas pedal to keep her running while waiting for a construction crew to clear the road on my way back from a battery purchase. (Details in previous post) After checking codes, fuel pressure etc. I decided to replace the TPS and ISC motor as a precautionary measure. Well, let the fun begin! First of all, the idiot who installed the TPS over torqued one of the attachment screws and it broke flush with the base housing. So he glued it in! Everything has to come off the intake to remove the base so it can be drilled out and retapped. After 36 years the bolts for the attached parts are gaulded to the intake as are the various pipes etc attached to the fuel intake base. And trying to get to the mounting bolts and connecting tubing requires removing other sensors, also gaulded, along with the distributor. A real nightmare, I don't look forward to removing the intake manifold to drill out all of the twisted off bolts so in a flash of possibly unsophisticated thought, I am thinking to just fugetaboutit and remove the TPS and ISC motor completely. After all I can adjust the idle up or down with the throttle screw. Don't think it would be a big deal to do that, might set a code or two, but so what? The TPS and ISC are only idle control functions and seem, at least to me, to be add-on electronic gizmos that add nothing to the run-ability of the engine, just being idle control.

I am probably missing something in my reasoning, (trying to save a lot of additional work and aggravation) and would appreciate any input from anyone who has been faced with a similar situation. And,as an addendum, NO, the base cannot be drilled out while still in position on the car.
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Scooter, I can tell you driving without a working ISC is no fun. But it is possible.
My ISC was on the fritz so I disconnected it temporarily. Lots of stalls after cold starts, some stalls even after warm starts. I couldn't use AC because the car would stall at a stop, mid drive (insufficient RPMs). I'd have to rev the engine in Neutral to keep it running before putting it in gear, which, of course, caused a jolt when you put the car in gear. That requires some running room to do safely. One time I took out a wooden fence overdoing it in reverse.

Can't be re-tapped, a little bigger?
I have a fix for the antenna. Cut the mast off carefully with a hacksaw blade and tape over the hole :) That's what I did.

You're probably aware, but if you don't calibrate the ISC and TPS perfectly and at the same time, it'll never work right. It's real hard and the steps in the FSM must be followed. Even pro mechanics will screw it up because they approach it like a modern car and wrongly see no need to follow the steps in the FSM. There are no shortcuts for that calibration.

Smokus will probably chime in again soon... do what he says. He knows this stuff.
p.s. I'm just a parts changer, but in your situation I'd consider screwing in the TPS screws again, using the existing holes, but with Loctite. Seems possible that might hold, even if stripped. I would not, however, use anything permanent or stronger than thread locker.
p.p.s. Reread your first post: Oh, the mechanic broke the screw head off, so the screw shaft is stuck in there, with no head? Yikes.
Apparently Christine is a Seville, which checks out. My EldoradO is clearly male.
Related: I once met a woman named "Eldorada," named after her dad's favorite car. (She said: "Hi there, I'm named after your car...").
I greatly appreciated the attention to gender/suffix naming convention.
At first, I started down that fender-removal route, hoping to save the mast. But stopped halfway, then never got around to finishing removal, then needed a car cover... so simply cut it off. I really wanted to make it work, just because, and if I still had the mast I'd probably try to rebuild it using steel cored weedwhacker line and Gorilla epoxy. But that antenna ship has sailed for me. New mast is like $140.

The ISC/TPS calibration is a well-known PITA in the HT4100. People here say it's actually achievable by a layman. If mine requires recalibration again, I'll give it a go, but last time I gave up and paid a garage to do it. (By the way, that garage screwed it up the first time and I had to insist they do it again, correctly, following the FSM).
... surely there are dozens of "how to calibrate the ISC/TPS" threads on here. Poke around.
Consider something like this?:

Advertised as good for as small as 3mm (a 3mm screw head, that is. But I figure the screw shaft in your case may be about 3mm. Do I know what I'm talking about? No).
So Scooter, it works now? Congrats on the screw hole fixes.

Curious, what's a "$1,000 diagnostic reader"? Since an HT4100 doesn't have any standard OBD ports etc. I had thought any modern tools were useless with regard to the ISC/TPS calibration.
That sounds right, though I haven't ever done it or looked at that section of the FSM in a long while, thank god.
So the TPS/ISC hasn't been dialed in yet? I can tell you that the pro mechanic who did mine said basically, "I don't need to follow all the steps in the manual. This handy modern tool I have makes it much easier." And then he screwed it up and I had to take it back.
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