I bought this car to use as a daily commuter car - my wife needed the Magnum to haul the kid around a few days a week, and I was driving my Suburban or my Electra to work on those days. Both have older carb'ed V8 engines that use tons of gas and are in various states of "needs work". When the brakes went out on the Electra one day, I figured I could spend a few hundred bucks to make one of them decent, or just get a smaller commuter car that I cared nothing about and that was better on gas - so I had more money for fun stuff. At the time, gas was hovering in the $4/gallon range, so it made sense. The result of that hunting was this car - Craigslist scores again.
The car is a pretty basic setup that is very similar to the Lumina I parted out - it has a 3.1L V6 with multiport EFI, front wheel drive, a basic set of options, and the typical peeling/worn out paint on all the horizontal surfaces that the GM's of this era are (in)famous for. (Thank you EPA and CARB for forcing a switch to water-based paints before the quality was there. But, I digress...) The exterior is black and the interior is a tolerable red that's in pretty good shape for it's age. The bonus here is that it's the sportier 2 door "Euro" model with full instrumentation (tach, oil pressure, water temp), factory alloy wheels (with decent tires on them), bucket seats, and a console shifter for the automatic trans. All in all, it's a nice improvement over the typical boring 4-door family hauler Lumina models. The power windows, AC, and cruise control all work, as does the factory radio. It even has a power trunk release, though I didn't find that until after I'd owned the car for a while. The engine is nearly spotless and the spare has never been down. The trunk is in good shape and is very clean with all the factory trim present. All together not bad for the $1000 I paid for it - including the required tax, title, and license fees. The Euro package means better handling, so it's not quite the mushy slip-'n-slide handling of most of these cars. It's not stellar by any means, but it's not bad either. It's got low mileage for it's age (~84,000), the engine runs nearly pretty good, the trans shifts fine, and overall it's pretty tolerable to drive. Not quite as much fun as the Magnum, but tolerable. These are well known to be long-lasting cars, so I should be able to get good use out of it over the next few years. And, if at some point in the future the car keels over, I can grab all of the EFI parts to use on one of my EFI conversions, and I can part out the rest to recoup costs. With the monthly gas savings compared to the Suburban meaning it will have paid for itself in just a few months of use - knowing that I will actually get something out of it when it's all said and done, well, that makes it an even better deal. Oh, and did I mention the the AC didn't work in either the Suburban or in the Electra (at least not when I bought this car)? Yeah, AC is a nice feature in your daily driver - sweating it out in traffic after a long day at work is no fun...
This is the car when I first bought it.
This is the car when I put it up for sale.
Trunk and engine compartment:
Option list (on spare tire cover in trunk):
These are the option codes from the sticker in the trunk.
Repairs and Maintenance
When I got the car, I quickly figured out it had a few minor problems. The idle was a bit unstable, the engine cut out past 3/4 throttle under load, and under moderate load, the AC/heater switched to blowing out of the floor vents instead of the defroster or dash vents. All in all, pretty minor. The engine didn't have any trouble codes, but the 3/4 throttle cutout was very annoying as was the AC/heater vent issue. So, I decided to dig into them and see what I could find out, and use this car as a running example of testing and monitoring the EFI system since I was planning on using this same basic system as a basis for one or more EFI conversions. My first step was to check the manual and see what seemed to be common on various complaints. Low vacuum seemed indicated by the heater/AC issue, and the full throttle cutting out seemed to be fuel filter related. I swapped the fuel filter - no change.
At this point, I decided to get serious and find a ALDL cable and hook up the EFI system to a laptop computer and see what the computer was reporting back for various stuff - once you get it going, you can monitor the EFI system in real time and even do data logging of a test drive to go back over later. If some sensor is getting out of whack, it'll show up in the data and you can usually zero in on the problem pretty quickly. So, I researched things and bought an ALDL to USB cable to hook up to the wife's laptop (no serial port, so I had to go USB), downloaded various bits of software from the web, and tried it out on the car - no luck. I couldn't get any reasonable or intelligible data out of any of the programs I tried. Even worse, for some reason, after hooking up the ALDL cable and futzing about, now the car refused to start or run. Uh-oh. What the heck had I done? At first I thought it was something dumb - low fuel, since the gas was low to start with and I had been sitting futzing with it for a while in the driveway, maybe I just got low enough to uncover the pickup in the tank. So I added some gas from a gas can, no change. After some puzzling about, I decided to try swapping the EFI computer for one of the spares I had laying about - it was free, and swapping out parts is often helpful in determining what's wrong - if you have access to the parts. The replacement ECM out of the 1992 Lumina I parted out got the car running, though it ran very poorly and only idled - as soon as you gave it any gas, even just breathing on the accelerator pedal, it died. Hmmm.
I then turned my attention back to the ALDL cable and did some more research - it looks like most ALDL to USB arrangements won't handle the 160 baud serial data from the older EFI computers like this car has; something about being unable to program the serial port to be slow enough. These cables all use a serial to USB converter internally, so it's actually a ALDL to serial to USB arrangement. Wasn't this lovely - I took a running car and reduced it to a brick. Great first try for EFI data logging, huh? I talked it over with a buddy, and we came to the conclusion that something else must be going on - maybe the original ECM was on the edge to start with (that full throttle thing was somewhat weird) and something as simple as hooking the ALDL cable up to the ECM pushed it over the edge. I can't possibly imagine how the ALDL cable could have screwed things up this badly unless something else was already wrong and I just got dumb lucky and it fell over at the same time or something in hooking up the ALDL cable pushed the ECM off the cliff. I have al the luck sometimes.
Next up was more troubleshooting without the ECM and computer goo - good old fashioned stuff, though I did use the basic code reader I had for this car that flashes the trouble codes on the "check engine" light. It was now spitting out code 33 - "MAP sensor voltage high" which translates into low vacuum at the sensor. The book cautions that this could be a bad sensor, or it could be something else causing the vacuum to be low. So, I swapped out the MAP sensor for a spare from the 1992 Lumina I parted out - no change in behavior. I then hooked up a vacuum gauge and verified the vacuum was, in fact, low - it was. I started tracing vacuum lines and make sure nothing had fallen off, and I didn't find any immediate issues. I then tested the vacuum close back to the intake - right at the fuel pressure regulator - no change. More tracing of vacuum hoses lead me over to the cruise control module on the driver's side inner fender, and I found a small vacuum hose that dove down under stuff - tracing it down, it went all the way down under the frame and hooked to...nothing. I had a wide open vacuum line, and there were mounts down there for something - the vacuum canister! OK, so at least I had likely solved the mystery of the magically switching AC/heater vents, but plugging the vacuum line and re-testing the engine didn't change things, so something else was still wrong. I broke out the mechanics stethoscope and checked the injectors - they seemed to be working right. Battery voltage and the fuel pump relay checked out OK as well. Hooking up a spark checker showed a regular spark, though I couldn't tell if the checker was showing a weak orange spark or if it was supposed to be that way. I was still generally puzzled, so I slept on it.
I needed to check the fuel pressure next - all signs pointed to a fuel issue at this point. Since this was my first major EFI debugging task, I had to go get an EFI fuel pressure tester - Harbor Freight is great sometimes. I hooked it up, and got 40PSI with the key on and engine off - which is right at the low end of the spec, but still within spec - but the pressure didn't drop when the engine was started. I checked the regulator with my hand held vacuum pump, and got the expected 10PSI pressure drop (down to 30PSI) from full vacuum. So, the regulator was OK, but was not getting enough vacuum to drop the pressure down at idle (or whenever there was high vacuum). There was no real surprise there; the engine was not making much vacuum to start with - it was barely running - so the regulator couldn't do much of anything without any noticeable amount of vacuum being applied to it. As far as it was concerned, there was no vacuum, so pressure stayed high. I did note that the fuel pressure was nice and steady with the engine running - so the pump + regulator were doing a decent job of maintaining 40PSI and not bouncing all over the place. So, now I knew I was getting good fuel pressure. Hmmm... Another night to sleep on it and thing through the issues. I did manage to find a new vacuum canister at my local parts store for $15, so I tossed that on there - no change in the engine, but it felt good to make some plausible progress, even if it was for something non-critical.
I futzed around with various other small stuff, but nothing made sense and everything pointed to the injectors as the next place to check, but that required pulling the upper intake. At this point, I was out of spare time, leaving on vacation, in need of getting the car running, and out of ideas other than pulling the upper intake and cleaning/checking/rebuilding the injectors. Since I didn't have time to do that, I took it to the local shop I use and let them diagnose/fix it. They ran down the same tests as I did (and complimented me on my thoroughness - I gave them a detailed list of what'd I'd done), and then concurred they needed to dig into the injectors. I had two plugged injectors, one dead injector, and the other three just needed a good cleaning. I'm guessing that the "dead" injector was sort of working, but that my guess with the fuel filter was not unreasonable. The car had sat, so all sorts of gunk had been in the tank from the gas turning to sludge. Run the car for a while, and you shake loose a good bit of it. I basically ended up paying retail for a set of reconditioned injectors to the tune of almost $300, plus the labor to diagnose it, and pull the upper intake, yank the injectors, and put it back together again. About $500 total, but it came with a guarantee, and I had a running car when I got back from vacation. Oh well. At least I got a chance to do some EFI troubleshooting and learned that my instincts for where to go next were on target, even if my schedule didn't allow for me to explore that further at the time. But, my $1000 car was now a $1500 car plus some valuable learning experience. :-/
It later stalled out on me again, and was traced to a bad ignition controller - this is the part the coils mount to. It was replaced with a brand new unit and that improved things a good bit. The car has had intermittent stalling and idle problems after that and I don't have time to chase them any more, so I'm selling the car.
The radio worked fine when I got the car, but the speakers developed some annoying problems pretty soon - I originally thought the speaker cones dry-rotted to some degree from sitting in the sun and lack of use. Then, the radio developed some really loud and intermittent popping and static while you were driving. At that point my guess was one of the capacitors had gone bad inside the radio or connections were loose somewhere in there. So, I bought a replacement radio off Craigslist for $30 from a 1992 Lumina plugged it in, and was happy to have tunes again. Why didn't I save the radio from the parts car? Um, yeah... Live and learn? I was really surprised at how often these radios show up on eBay. Used factory stuff is pretty cheap. Sure, not all of the faceplate lights come on, but it's enough to work, and the sound part is functional, even if the right speakers are a bit softer than the left no matter how you twiddle the balance or fader controls. For $30, I've got tunes - and that's enough to keep me sane driving to and from work in this thing. I can even hook up my Zune car adaptor, and I can get tunes that way - who needs a CD player? It does the job.
Stuff To Do and/or Fix
Page last updated 04/26/2010 08:01:52 PM