Gojira94

1) key on with cruise switch in 'off' position (lamp 4 on only) 2) cruise switch in 'on' position (lamps 2, 3, 4 on) 3) brake pedal pressed (lamps 2, 3 off, lamp 4 remains on) 4) brake pedal released (lamps 2, 3, 4 on) 5) 'resume/accel' button pressed and released (lamps 2, 3, 4, 5, 6 on, then back to 2, 3, 4 only) 6) 'set' button pressed and released (lamps 1, 2, 3, 4 on, then back to 2, 3, 4 only) 7) cruise switch from 'on' to 'off' and 'on' again (lamps 2, 3 go out and back on again, lamp 4 remains on) 8) brake pedal pressed (lamps 2, 3 off, lamp 4 remains on) 9) 'set' button pressed and released (lamps 1, 2, 3, 4 on, then back to 2, 3, 4 only) 10) 'resume/accel' button pressed and released (lamps 2, 3, 4, 5, 6 on, then back to 2, 3, 4 only)

If you want the 823, Dimar Motorsports on EBay has them but only in sets of 8 for $200. I got these from them and could not be happier: 0 280 155 702 EV6 Long Jetronic 4-hole 200cc/min 16 Ohm (mid-90s Volvo 960 injectors) https://www.ebay.com/itm/283645389229

REM is on the way via USPS, should be there Saturday. I also enclosed a new NTK sensor. It's one of the newer metal body design. I ended up not using it since I found a ceramic body NOS AC Delco 25176716 that gave me a perfect 6.2 ohms on the heater grid circuit. I measured the heater grid circuit resistance of the NTK and it's just a hair below spec at 4.8 ohms but I thought it might be useful for troubleshooting.

Ok good, my bad. And my bad for the wrong numbers initially.

If your reading is 2060 k ohms, that's crazy low temp equivalent. If it's 2.060 k ohms (2060 ohms), that corresponds to about 90*F. So, after 4 minutes run time and a 2 hour cool-down sounds about right. Values corrected in this post and post a few back.

2060 on k-ohm would be a little over 2 million ohms (2060 x 1000 ohms). My Fluke 87 has a max of 5 digit places plus a floating decimal point to work with, not sure about yours. I'd like to be really really sure about this sensor before we move on. Post a pic of your reading? Consider this scenario... Upper peninsula of Michigan in mid-February, -38* (70* below the freezing temp of water) and you've got the best Prestone antifreeze in history. The density of air at that low a temperature has almost 50% additional more oxygen molecules per cubic meter than it does at +75* (1.647 kg/m3 at -38F vs 1.105 kg/m3 at +75F). Cold start is going to require a significant addition of fuel to get the engine started. More oxygen molecules in the air, and by extension the temperature of the engine based on measuring the coolant temp, means more fuel is required for an engine to run at all, somewhere between 10.5:1 and 16.5:1 air/fuel ratio. Coolant temp in the real world wouldn't get quite as low as the air temp, so this isn't a scientifically/ mathematically accurate scenario, but you get the idea... So you can imagine, a bad coolant temp sensor can fool the computer into thinking it's magnitudes of degrees colder than it is on a 77-93* day in Texas, and drown the engine in fuel immediately, whether on a cold start or hot restart.

I'll be back in town today and I'll get the REM on the way to you. I had another 'coulda had a V8' moment. Your CTS on the driver's side of the block needs to be checked. If it's electrically open/ failed the ECU would think it's -40F all the time and would create the super fat rich condition. If you have a meter set it for k-ohms, unplug the sensor and check it. If it reads between 1.8k ohms (1,800 ohms) and 3.4k ohms (3,400 ohms) cold it's ok. If it's OL/ infinite it's bad. Anywhere above 4,000 ohms it's junk if it's hotter than 55*F outside/ cold motor. -40*F would be 100,700-ish ohms FWIW.

No dice on resetting the low speed to about the 10-11:00 position yesterday. Pots A and B feel a little crunchy, C feels smooth. I suspect the regulator is toast due to dead pot(s). When I get back in town I'll pull it back out and see about maybe ohming them out on the circuit board while turning to confirm dead spots. Long time ago there was an electronics repair place about an hour west in Durham, NC. Nothing else looks wrong with this regulator.

Unless I've missed something, everything checks out electrically with cruise control. Vacuum also checks out. The dump valve is 100% good. Just now I was looking at the potentiometers in the regulator module. I haven't moved any of the settings since I harvested it from the boneyard. Lo and behold, the low speed limit is maxed out. Before, I'd tried engaging it around 55-60MPH per my speedometer. Might have worked if I was doing 70-75 lol. I need to get some chores done but I think I'll be taking a test drive today.

If you have Prime, this is a fun little show from around 2017. A couple of English guys buying cars for under 1000 pounds and re-selling with a 5-day turnaround. Season 1, Episode 3 1993 Volvo 480 SE (Renix Volvo) Punchline delivered at 19:30...

In general, no. We're having you go through and check things to work backward to the cause. At a high level, running rich on an EFI system has 3 causes: 1) too much fuel pressure or faulty injectors leaking/ delivering more fuel than designed/ intended 2) extra air getting in somewhere that's not accounted for by the computer - the O2 sensor then sees a lean condition and the computer commands more fuel to compensate 3) Inadequate spark to burn the fuel delivered

One more thing - pull the distributor cap if you haven't yet. Leave the wires on it, and have a look at the rotor and the cap contacts. And try to rotate the rotor by hand. It should have a really tiny bit of wiggle to it but not a lot.

Fuel pressure is fine, not an issue. A piece of hose and a bolt is a time-honored method of plugging a vacuum port lol. I'd say leave that in place for now while troubleshooting continues. There are plenty of places for vacuum lines to crack near the vacuum tank and the check valves may not be healthy enough to hold vacuum. Once the issue is solved, you'll want to investigate and patch up any other other vacuum line breaks, and see if the vacuum tank still holds. Maybe even get cruise control back... Meantime, I think you're on the right track to try to confirm a cracked exhaust manifold. And the O2 sensor may be dead or contributing to the issue if it's commanding more fuel if it's seeing what it thinks is a lean condition from cracked manifold. When you turn the key on prior to engine start, do you see the 'Check Engine' lamp light up during the lamp check? I wonder if the bulb might be burned out and would otherwise be illuminated. I'm willing to loan you my REM, I don't have any immediate need for it. PM me with info and I'll mail it to you. I'm still concerned about verifying spark/ spark timing. More so with the distributor indexing than anything else. The coil and module are working, at least. The coil can be tested for primary and secondary resistance easily enough with a meter while the module would require a DRB II.

Maybe disconnect the battery briefly before you drive, just to clear out the short and long-term fuel trims. Let it start from scratch figuring out fueling...

If you're assembling everything off-vehicle you might try using the vent valve holes to sight-in locating the return pipe/ rubber foot into the raised round locator for it inside the tank. If you're on that for sure, you may need to slightly tweak your assembly to get it to line up. Usually once you get the foot in place you have a decent amount of wiggle to get the top plate lined up.

My concern is there's a vacuum leak somewhere on the other end of that hose you pulled, and isolating the engine from that with a cap might make a difference. You'd temporarily lose HVAC controls (defrost-only mode) and any hope of cruise control working but it will help diagnosing driveability by eliminating a family of potential vacuum leaks. We do expect the fittings on the manifold themselves to be pulling vacuum. The idea is to work the throttle with that fitting capped. If it takes throttle and doesn't pop/ bog/ want to stall, then we're getting somewhere.

Let's take a stab at something that's been bugging me. The main vacuum feed for HVAC, CAD, cruise and vacuum tank. Anything downstream of that could introduce a really big vacuum leak you wouldn't detect spritzing water or starting fluid around the intake. Put a vacuum cap on the fitting circled in red and see if it makes a huge difference. Call it a 'slaps forehead and exclaims "I coulda had a V8!" moment.

Poor fuel mileage, hesitation or backfire/ pop on acceleration, lack of crisp throttle response, sooty/ fouled spark plugs, shortened O2 sensor life, fuel poisoning of the converter, running cooler (or hotter) than normal, fuel contamination of the oil (washes the rings, accelerates cylinder wear), dramatic increase in HCs and raw fuel smell in the exhaust, to name a few...

That's for lower pressure, 4-12psi (carbs). This one ($29.99) would work: https://www.harborfreight.com/fuel-injection-pump-tester-58760.html

If the oil was getting heavily fuel contaminated, the dipstick would stink of raw gas. Sounds like you're ok there, so you likely don't have an 'internal' fuel leak making it dangerously rich. However, I agree with Porquer that the plugs show very rich/ sooty, with the ceramic insulator completely blackened. I'd still go ahead and see what your fuel pressure is with the ballast resistor both hooked up and bypassed, it's just good to know. Bad news is you're definitely over-fueling, likely something with an exhaust leak near the O2 sensor as stated previously. The increased loudness, even after a muffler change, indicates either your exhaust manifold is indeed cracked where you can't see it, or possibly the donut gasket to the downpipe is blown. Hard to say for sure on marginally ok spark timing possibly adding to the mix of woes, but let's set that aside for the moment until we know more about fuel/air.

Thanks! I've already determined everything from switch to 'Speed Control Regulator' connector is good. Haven't tested the servo or regulator themselves yet.

Yes! I saw a fuller description in another listing that was asking $325.00 for one: "Used Dana Electronic Cruise Control Tester. The Part #250-3122. This tester will test the cruise control and speed control. The tester comes with Harness Adapter. Dana Electronic cruise control tester, for systems supplied to car makers and aftermarket installation companies. Dana was the supplier of choice for several car manufactures, including Ford. They also supplied cruise control systems for aftermarket installations at many specialty shops and dealers. This electronics tester facilitates the testing of Dana systems with ease. The tester allows for proper calibration of the low speed setting as well as the accuracy. This tool is used with OBD 1 era and legacy cars."

I really wanted a CJ when I was a kid in the 70s-early 80s. There's an EBay seller here in NC that has 258 and V8 NOS sealed in AMC/Jeep box cruise kits. Saw them when I was looking for a tester. Pricey, but here's one: https://www.ebay.com/itm/127844355284

I'm hoping the documentation will reveal what other vehicles are covered with the harness adapter, that will be interesting to know!

I just scored one on Ebay. $15.00 + $7.50 shipping Part #250-3122 / 59C-02425 / AM PC-1-R I'll do a writeup with it after it arrives, since I just started diagnosing a non-functional cruise system. I strongly suspect it's my brake switch adjustment but I saw this and thought it would add vintage fun to the equation.