ABS trouble on a 1991 Cutlass Supreme

[peeeot]

Always learning! Well, the thing that I called a resistor is in fact a diode, and it was not malfunctioning. Indeed, I have learned without a doubt that there is nothing functionally wrong with the motor relay, and that I have wasted my money buying a new one (which hasn't shown up yet, btw). Maybe not a complete waste, because the contacts are pretty tired looking on the original relay, but still... I stumbled upon a diagnostic chart in the manual for code A036 and used it to determine that it is the accumulator pressure switch I need to replace. If I jump the A and B terminals of the switch connector, the pump motor will run every time. I was clued in to the need for a closer analysis when a 9v battery connected to the A and D terminals of the relay closed the contacts easily and consistently.

 

SO. What to do now? To fix it, all it needs is the pressure switch. Should be around $140 from gmpartsdirect.com; I'm not aware of any lower price elsewhere. It would take at least 3 weeks to show up, and I need a car to drive in the mean time!

[peeeot]

So, in a bit of a stroke of luck, the relay that I ordered has been put on a kind of backorder and the order was cancelled. So I don't have to pay for something I don't need! The only thing is, I hope the same thing doesn't happen to that pressure switch.

 

Another interesting note: I was doing some work on the horns when I discovered that the vacuum line to the vacuum tank under the fender was disconnected. I fixed it, and now the car drives waaaayyy better. I always thought it was underpowered, but it turns out it was just suffering from vacuum leak! It accelerates faster now with LESS throttle, is quieter and smoother as rpms build, and is generally much more enjoyable to operate. Added plusses are that I no longer get hot air on my feet, which I thought i felt sometimes before, and also cruise control will probably do a better job of maintaining speed on inclines. So... yeah, I never would have guessed such a tiny vacuum line to make such a big difference in so many different things.

 

EDIT: I still get the hot air on my feet. I was mistaken.

[Crazy K]

vacuum line? thats hilareous! those lines break alot. two of my cars have lost their vacuum resoirvoirs. guess I should remember to list that as something needing checking when you get a car period.

 

still selling? I still think you should keep it. but as lonag as it gets a good home.

[peeeot]

You mean lost the reservoirs as in they stopped holding vacuum, or they fell off?

 

I would have known there was a vacuum leak if I had a spec for intake manifold vacuum and had taken a reading. It probably would have been low. That's one of those things you used to check the operation of old cars but that I don't hear about as much in diagnosing new ones. I never would have known anything was wrong. Now I need to double check and make sure I don't have any other vacuum leaks I'm unaware of.

 

As for selling-- I continue to flip-flop several times daily about what to do with my cars, this one included. I don't know how I'm going to reach I final decision. There are a couple of things I'm wondering about pertaining to the convertibles though... Like most others, the side belt moulding weatherstrip on my car is pretty crumbly. Is that strip available anywhere? Perhaps because it's uneven, I've had frequent problems with the belt weatherstrip prying the sail window strip off the glass as the top folds down. It's really annoying when it happens.

 

I've searched the forum a bit on this, but I'm not clear as to the answer... have you (or anyone else) had any luck installing a top yourself? I would pretty much have to do it myself. Don't have $1000 to throw at that.

 

While I'm at it... How often does the rear pump housing fail on PM III? How reliable are the climate controls and mechanisms?

 

If I were to keep this car, I would be keeping it a long time (especially compared to how long I've kept others I've had). I want to make sure that I'm not going to experience failure of components that I'm not going to be able to replace/repair due to the unavailability of parts.

 

You see, one of the reasons I'm so attracted to certain old cars as daily drivers is because, due to their classic-ness, I can expect pretty much every part related to drivabilty to be available for a long time. With new (post-80s) cars, I get the impression that they are generally treated as disposable--drive for a couple years/130k miles and move on. I don't forsee parts being available for very long. I've often wondered how, and whether, cars from the 90s would ever really be collectors items, restored and cared for the way some old cars are. Sure, people restore cars that don't have a good parts base, like Frazers and Kaisers, but they have to have a lot of money to get what the need made if it can't be found. Imagine trying to get someone to make the pump motor relay for the ABS system of a 1991 CS in 2015,2020, 2060. I can hardly get one now... and where would I get the specifications for it I'd need to pay someone to make it? It's this sort of line of thought that bothers me about keeping the Cutlass more than anything right now. If I knew I could make it like new given time and effort, I wouldn't be nearly as nervous about keeping it around. But since some things are already gone and others not getting any easierto find, it makes me feel like I'll have to take the disposable attitude towards the Cutlass, and for some reason I want to be attached to my cars. At the same time I see how it could provide good enjoyment and service for several years. It would make good pracitcal sense.

 

So anyway, I'm pretty much always thinking about what to do and will hopefully arrive at a concrete, definite choice in the near future.

[peeeot]

Guess what? I got an email from gmpartsdirect.com stating that the pressure switch is discontinued and no longer available from GM. Where has everyone else been getting their PMIII parts from?

 

I got the accumulator from Prior. Do they sell other components individually, too?

[Crazy K]

I'd post that question in the turbo GP forum. sorry, I myself do not know. maybe prior makes one.

[peeeot]

Thanks, will-do!!

[peeeot]

AT LAST! I have secured and installed a replacement pressure switch and experienced a brief test drive with NO WARNING LIGHTS and constant power assist! It looks like by brake woes are over, hopefully for a long time!

 

Thanks again to everyone who has helped me get this figured out! I would have been completely stuck without this forum.

[Crazy K]

glad to hear it!!!!