What's new

The Blue & White Whale -1990 GMC 2500 Suburban...

toocheaptosmoke

Dollar Save Club
Joined
May 19, 2020
Member Number
212
Messages
175
Loc
PA
Not sure how this happened exactly, but I now own a 1990 GMC 2500 Suburban...

Couple months back back a friend asked if I would be interested in a southern, square body suburban, someone he works with had one they wanted to get rid of. So of course, I was like yeah, for the right price I'm always interested. It was conveyed that this was a southern vehicle, very solid, 4x4, etc. I kind of need another vehicle in the fleet (that's debatable...) with multi person and multi season capability, so the proper rationalization was employed. All was good, hopefully we'd hear back and go check it out. I've kind of wanted a square body suburban for while anyways.

Fast forward to this monday; Get a text saying "Remember that burban?" Turns out that the seller ended up just taking it to a semi local equipment auction. Great... Guess they didn't want to deal with, or think it would sell locally first... I figured it would end up bringing $$$, so kind of wrote things off at that point. The auction was ending on mid-week, and i didn't have time to check it out in person.

Auction day: During lunch I check back in on the action site just to see what kind of crazy money that sub is bringing. To my surprise, it's still sitting at $1700. There's a handful of pics on the listing, and they definitely look to be pretty decent and solid looking, no blown out wheel wells or rockers. Mileage is listed at 314k, newer tree-fiddy motor, just rebuilt th400, new tires, etc. At this point my mind starts turning over options, and it somehow landed on the option of needing to bid on this...

I sign up on the auction site, seems kind of "low budget" and spartan, but whatever. Back in my ebay days I used to snipe bids in the last 10 seconds, but with this new and unfamiliar system I didn't want to cut it that close. Figure wait until the last couple minutes to chuck in a bid. Not going to lie, this was bid slightly out of spite, sill a bit salty about not getting to try and do the deal locally first... Bidding time is running down, agonizingly slowly, and things start jumping, up to $1800, then rapid fire up to $2400. Things stall there, until the last 20 seconds, when it hits $2800, basically my top dollar! :eek: The clock ticks down to zero, but then starts blinking, some kind of "soft close" jack-offer-ey where you can keep extending the auction by bidding within 60 seconds of closing...

Eventually the auction finally closes, still at $2800, I can finally breathe. WRONG. The screen reloads to a page that says you "MAY HAVE WON." WTF is this shit!?! :laughing:

20211117_172539x.jpg



The next day I eventually got an invoice confirming I did indeed buy this thing, along with owing all the extra buyers fees and premiums... :shaking:

Things to be continued...
 
Great, now I have to go retrieve this thing... The utility trailer had been needing new boards on the deck for about 3 years, so no time like the present to go buy lumber and finally do the job. It was getting to the point where the soft spots out numbered the solids.

Just one problem: the trailer isn't wide enough to squeeze a fullsize axle width through. Have had a backup plan for just this situation, but never actually had to implement it yet. The fenders are not drive-over rated, but with some strategic board placement, I think you could make a strong back to drive over. The trailer is a 1997 7000 lb generic variant, in 20' deck length.


Wanted to add more triangulation and cross bracing for board support and rigidity, but ran out of time. Will have to re-visit this later. (yeah right...)

20211120_142900x.jpg




There was zero sketchiness involved with picking up the 16' boards...

20211120_135012x.jpg



Safety Bulletin: If you've had too many beers to correctly operate a circular saw, just stick with the chainsaw...

20211120_173922x.jpg




Done. Just in time for rain to soak the un-treated lumber.

20211121_135449x.jpg
 
Got the trailer back together, checked the bearings, fixed some lights, and good to go. Trailer may or may not be inspected, so try to keep everything from being excessively sketchy... The old Carlisle USA trails are still the originals from '97! They don't make 'em like they used to.:smokin: Had about an hour drive to the yard.

Arrived to the auction site, verified that the white whale was still there and not stolen, then went through the painful task of paying the auction debt, notary costs, and various other service fees...

20211122_122025x.jpg



Luckily it was parked on a downhill slope to make loading more fun. I gave things a brief once over to see what we were getting into. First impressions were slightly disappointing, definitely a little bit more rust than I was hoping for, although far from being roached out. But, it was bought and paid for, load it up and check it out better later on.

20211122_124609x.jpg



The drive over fender ramps, made from an old bed frame, actually worked quite well. Although, could have probably stood to be three boards wide. Tried to hack together an electric boat winch for the trailer the night before, but that failed, so back to manual labor.

20211122_125902x.jpg


20211122_131011x.jpg



Once the front end was up onto the trailer I started realizing how much heavier this thing was than first thought. It was lifting the back of the dodge up off the ground. Put the jack to work to get things leveled out a bit. Did I mention the trailer tires are going on 25 years old? :homer:

20211122_131054x.jpg



Time to hit the road. :grinpimp:

20211122_134309x.jpg
 
It prob weighs more than the dodge does.

I'd believe it

Any idea why it doesn't run?

Supposedly it fires off fuel dumped in the throttle body, but doesn't stay running. Going to check fuel pump and any relays/fuses first. Battery that came with it looks to be taking a charge, so we'll give it a go here soon.
 
Here's some pics, trip home was uneventful. The main reason I was interested in this one was the fact that it was supposedly a pretty much rust free southern/western vehicle. Even if there was a rod hanging out of the block, I'd rather swap drivetrain parts all day if it meant no rust. (you guys not in the rust belt suck :flipoff2:) It turned out to be pretty decent, but certainly NOT rust free... That's the chance you take not seeing things in person, oh well. :homer:

Listed Description: 314,389 miles, 3/4 ton, 350 engine, rebuilt turbo 400, 3.73 axle gears, posi rear end, New Tires, 135k miles on engine, 134A AC, third row seat.

20211123_164337x.jpg


20211123_164500x.jpg


20211123_164422x.jpg


20211123_164444x.jpg


20211123_164511x.jpg


20211123_164556x.jpg


20211123_164700x.jpg



The tires are most definitely NOT new...

20211123_164635x.jpg
 
Really short term plan: Try and get running, possibly drive on road a bit as is to see what all else is wrong with it.



Short term plan: Go through it and get it reliable enough for tow pig duty, with some drivetrain changes.

- Engine: If it runs well enough, probably just use it as is. Not going to be a power house, but my expectations are low... Has TBI, but not gonna lie I'm tempted to throw a Q-jet on it.

- Trans: My first thought was since GM made a million of these trucks, it ought to be cheap and easy to just throw a 4 speed it it and rock on. Not sure how easy this actually going to be though? Seems there are differences between the hyd. clutch setups, bellhousings, bracketry, driveshafts, T-case inputs, etc. I just want to get rid of the automatic, but hopefully not fall too deeply down the rabbit hole...

- T-case: NP241, got to figure out what needs to change there

- Rear Axle: Possibly just leave the stock one, but I keep thinking maybe I need to swap in a FF 14b?


Alternate Plan: LS swap, NV4500, plus whatever else. Really didn't want to get into this right now, but if a 4 speed swap is gonna cost a fortune it will be hard to justify.
 
Current status: Trying to get the engine running.

Have verified that fuel pump is turning on when key is on. Don't have the fitting to verify pressure, but fuel is reaching throttle body. Fuel pump runs for ~20 seconds then stops.

Engine fires on gas dumped in it, ignition seems to be working.

Fuel injectors are not spraying at all, during prime or cranking. When fuel pump is running and a 9v battery applied to injector, it clicks and will fire fuel. Hot wire on Injector plug is getting 12v.

Seems like the pickup in the distributor should be working if it's getting spark. ECMa and ECMb fuse slots are getting power.

Check engine light never comes on when turning ignition on. Have not verified if bulb is burned out yet. Verified plugs are solidly inserted into ECM. Ran aux. ground wire from grounding loop near t-stat housing to body ground, no change.

From what I've been able to find, the issue seems to be a lack of grounding signal to the inejctors. Whether there's a bad ground, wire break, or bad ECM, not sure yet.
 
Verify oil psi and that both sensors are plugged in.

I unplugged the sending unit by the distributor, a 3 wire, and jumpered the tan(?) wire to the gauge, it maxed out, no change. Briefly jumpered the other wire (gray?) to the hot orange wire, and it sparked and sounded like the fuel pump kicked on. Plugged it back in, when cranking it's getting up to 40 psi on gauge. Also tried unplugging TPS, no change.
 
You sure it has an NP241 Tcase and not a 208?

Also swapping a quadrajunk carb in place of the efi, well you deserve all trouble you cause yourself.
 
You sure it has an NP241 Tcase and not a 208?

Also swapping a quadrajunk carb in place of the efi, well you deserve all trouble you cause yourself.

Haha, I actually like quadrabogs! Got a decent amount of tuning components, and probably 3 or 4 non-emissions bodies laying around.

Edit: Quadrajets are like mullets, business in the front, party in the back!!

Was a bit hard to read the tag, but it looked to say 241.

20211123_183658x.jpg
 
Nothing wrong with 241 case, electronic speedo, good tcase to ls swap with.
Good to know.



Couple more things I'm mulling over trying to narrow down the (non) running issue, trying to avoid just hucking parts at it.

- This thing has an aftermarket security system, I've been able to work around with key and over ride button combos thus far, but going to disable at some point. The locks click as soon as you turn the ignition to off, not sure if this is the security system or factory? Most things I've found don't say the security system ties into the ECM

- One of the ECM fuses is a 25 amp, when it shoudl be a 10. Maybe a sign that something fried?
 
Verify oil psi and that both sensors are plugged in.

This won't keep the injectors from firing. One sensor is for the gauge, one is a failsafe incase the fuel pump relay fails. Crank the engine until it builds oil pressure, and it sends power to the fuel pump.

Make sure it has fuel pressure. Easiest way is to buy a tee adapter and screw it inline at the fuel filter, or maybe where the braided lines coming down the back of the motor connect to the hard lines under the truck, but you'll need to find one with the correct fittings (metric O-ring, IIRC). At the very least, crack the supply line at the throttle body and make sure gas comes out when the pump comes on.

Pete
 
This won't keep the injectors from firing. One sensor is for the gauge, one is a failsafe incase the fuel pump relay fails. Crank the engine until it builds oil pressure, and it sends power to the fuel pump.

Make sure it has fuel pressure. Easiest way is to buy a tee adapter and screw it inline at the fuel filter, or maybe where the braided lines coming down the back of the motor connect to the hard lines under the truck, but you'll need to find one with the correct fittings (metric O-ring, IIRC). At the very least, crack the supply line at the throttle body and make sure gas comes out when the pump comes on.

Pete
Yes, it's getting fuel to the throttle body, it flowed out when cracking the fitting. I can get the injectors to spray fuel when energized with a 9V battery, but nothing when when cranking or keyed on.

I tried disconnecting the ECM tonight to see if any check engine or dash lights come on, but nothing. The only dash light that comes on is the seat belt one.
 
You can use paper clips jumpers and a noid light at the ecm to see if the ecm is sending a pulse to the injections, if it doesn't this doesn't necessarily mean that the ecm is at fault but if it does have pulse then you'll know that it's a wiring problem.
 
You can use paper clips jumpers and a noid light at the ecm to see if the ecm is sending a pulse to the injections, if it doesn't this doesn't necessarily mean that the ecm is at fault but if it does have pulse then you'll know that it's a wiring problem.
Ok, may have to make up a noid light. I wasnt too concerned about using one at the injectors since I can hear they arent clicking, but doing it directly at ecm would help narrow it down more.

I also tried running additional grounds from battery/body/engine, no changes.
 
Noid light will help you confirm whether injectors are getting signals from ecm.

You said it sat for years. It’s a possibility injectors are stuck closed.

I just got my 97 TJ with 2.5 running like a sewing machine after sitting for over 15 years. I had to tap on injectors vigorously to get all 4 cylinders firing. :smokin:
 
Well, it runs!!

Checked pins on the ECM and its harness, verified the ECM was getting power. The ground also check out. Plugged everything back in and probed the check engine light circuit, it showed 12 volts. That lead me to believe the bulb was probably burned out in the dash.

Got frustrated enough to start throwing parts at it. First thing was the ICM, replaced that and still no go on the injectors firing. That was surprisingly painful to replace.

Next up was the ECM, figured screw it, would probably end up getting one for a spare anyways. Swapped that over and the service engine light suddenly came on! :idea: Thought we were home free, but no, still no injector pulse... The fuel pump however was noticeably louder now and would run for the correct 2 seconds after key on. Used 9v battery to fire some fuel into the TB and tried cranking, but now it wouldn't even try to fire. Went back to the ICM, where the connectors had been a bit stubborn to reinstall, and moved them around. Cranked it once more and boom, fired right off.
 
Top Back Refresh