Do you like Cadillac luxury at a convenient price? Are you familiar with the intricacies of an early 1990s Chevy V8 with Throttle-Body Injection? If so, this 1991 Cadillac Brougham may be your next hobby car/luxo boat/daily driver. Barn Finds reader Barney found it on craigslist near Portland with a clean title and an expired Washington registration. Priced at a very reasonable $3,000, there has to be a catch, right? There is – the engine dies at idle once it warms up. A mechanic hit it with the parts cannon to no avail, but maybe you will have better luck and grab a deal as a result.
I can’t imagine that an engine as comparatively simple as a TBI 350 should be that hard for an experienced mechanic to figure out, and when they (or you) do, you’ll be driving a 138,945-mile Brougham that looks like it has only 38,945 miles on it. The interior is extremely nice, with an uncracked dashboard and tear-free upholstery. Unfortunately, the ad is classic craigslist: short on information and not too forthcoming with pictures. The seller did say that their mechanic installed a new coil, a new distributor, and a new idle air control valve without solving the problem.
The 350 was a $250 option in the 1991 Brougham, by the way; the standard engine was the 170-horsepower 305, which I always find a little funny for some reason. A 305 in a Cadillac? Regardless, the 350 gave buyers an extra 15 horsepower and, more importantly, an extra 45 lb.-ft. of torque for a total of 300. Both engines used a 4L60E automatic transmission, and Broughams had a standard 3.08:1 rear axle ratio.
There’s no information aside from the engine’s maladies about what works or what doesn’t work. That’s too bad, because by 1991, almost every power convenience item you’d ever want in a Cadillac was standard equipment on the Brougham, including power locks, power seats, power windows, cruise control, automatic electronic climate control, power trunk release, rear window defroster, power heated mirrors, all for a base price of $30,225. That’s a lot of money for 1991, but at least the Brougham looked like a traditional Cadillac; at 221 inches long, it was well over a foot longer than the next biggest model in the lineup.
Yes, this Cadillac seems to have held up well to time and the elements. Broughams used basecoat/clearcoat paint in 1991, and this one appears to be painted a nice, elegant shade of “Light Antelope Firemist,” according to the paint chips at paintref.com. I can tell you one thing; if I lived near Portland and wanted a Cadillac, I wouldn’t be letting any TBI scare me. I’d be learning the ins and outs of the system and giving it a go, and if you have that kind of confidence (misguided or not), this Cadillac checks a lot of boxes.
I learned something new from Aaron today. I didn’t realize that Cadillac switched from the Olds 307 to the Chevy 305 in ’91. But Lo and Behold…… They did!! Its good to see this one was ordered with the 350 instead. Yes, it’s not a Cadillac engine, but it got the job done rather well I’m sure. ( especially compared to the HT 4100). ( Let’s face it folks….. Lincoln was using the “Ford” 302 for quite some time and no one was complaining) This one has held up
very well for the years and looks like it would make a great fun project to get up and running and enjoying. Great write up Aaron and a nice find Barney!!!
The last of that body style and in nice shape. You’re right, it doesn’t show like 138K!
The GM engine fiasco was something I didn’t understand from that era – they got in deep trouble, but meanwhile Lincolns used the 302, 351, 400, and 460 Ford engines and Imperial used the 312 or 440 Chrysler engines.
Why did GM get dumped on?
That’s a good question! It’s probably because unlike the others, GM divisions always DID use their own engines.
In reality, the Chevy small block was obviously a great engine, but I still think of a 305 as something powering my uncle’s Squarebody. For some reason, a 350 doesn’t seem so bad.
I came here looking for some troubleshooters to diagnose what could be the problem. Yeah I know it needs to be seen in person. But what about this, start with the fuel system, new lines or at least a new fuel filter to start, then Injector cleaning. If you can get it to run off a bottle replace the tank. If nothing else works I would replace that TBI. What were engine management controls like in 1991? Probably simple.my 1991 Mustang would start and then die and it was an Ignition control Module. Apparently Ford screwed up when engineering the placement of said module and the distributor placing it in a very hot area of the engine so they were prone to failure. I know different Make but GM probably had something similar. If it was closer I would take a look at it.
“The engine dies at idle once it warms up.” The engine runs in open loop until it warms up. Once warm it switches to closed loop and is using the sensors to adjust fuel/spark. It’s a sensor. TPS or the IAC valve.
Thanks Dave, I learn something new everyday here.
Possible electrical connection that opens when heated up? The auxiliary tank idea is a good one. I saw a diesel tank that a shop rag had fallen into. Upon acceleration, vacuum would pull it against the pickup tube, choking off the fuel supply. What does the (rudimentary) OBD say?
OBD1 can’t be read at the local O’O’O’ AutoZone. We’d have to go by blink codes. If it was close to me, I’d be all over this.
probably PCM failure, especially if it doesn’t store codes -that era of PCM can’t diagnose itself.
The seller closed the sale. It’s unavailable to us. Somebody snag it quickly for that price!! I knew people who had problems with this 350 setup. Pull the 350 and put in a crate 350 with a Rochester carb. Different distributor setup. And great running Cadillac. Still used the same exhaust system pass inspection. Just a idea that was done. 😄
This thing screams an upgrade to a 383 stroker while keeping it stock appearing and quite, a perfect sleeper.
With a stiffer gear outback it would be a ton of fun. Especially for my old behind that looks like I should be driving this car anyway!
If you think a 305 in a Brougham is funny, wait until you hear about the 249 that was used a few years earlier. My mother’s gentleman friend, a Town Car fan, owned one and commented that “it had to downshift to go over a speed bump.”
Absolute worst color for these 🤮
I had a ’77 Corvette that would die on the open road – not all the time but often enough to be an inconvenience when it did it on a desolate stretch of I55 in Mississippi … my wife and her friend were ahead of me on the way back to Chicago from New Orleans (it didn’t die on the way down) … turned out a gas line was too close to the exhaust and it would close when hot (sometimes) and the engine would die …funny thing – the service department in Jackson put over 300 miles on it for “test drives” to duplicate the problem (I left it there for two weeks) …
Could be a clogged catalytic converter. I had a ’78 Mercury Marquis and an Olds Delta 88 that did the same thing. May be a simple fix.