Crank, No Start on "new" '93 SL2 (77k!!!) UPDATE

[MiSaturn]

Well, stumped again.

Was in the process of inheriting a '93 SL2, when a no start issue popped up.

Hard time diagnosing OBDI, came up with Quad output issue and started tossing parts at the problem - crank position sensor, coils, wires, EGR, which made the people at Rock Auto happy, but didn't fix the no start issue.

Vehicle sat for the past five months, went out today to pick up where we left off. Put dead battery on charger while I drank more coffee and dreading what was next (plan was to do compression check to see if it had jumped timing).

Wanted to see if it had enough juice to turn over, hit the key and it started!

Ran somewhat poorly for a few minutes, but eventually warmed up and lifter noise subsided. Ran it around the block without issue, and was able to restart it a few times just to test my luck.

What I can't figure out is why it ran? Nothing changed/repaired since we last worked on it and frigid weather today wasn't any help. Next step is to take it to my regular shop and have them run some diagnostics to shed some light on its overall health.

My only guess/question, did letting the battery go down to the point where the ECM got reset and one of the new parts actually fix the no start issue. Realize that's a stretch, but it's all I've can think might have happened.

[billr]

You actually threw all those parts at it, but didn't check compression first???

When near-new, my '94 DOHC lost all compression on all cylinders, just sitting in my garage; then self-healed after a couple of hours. It now has over 250K miles, with no further issue, and I will probably never find the cause.

No, it is unlikely letting the battery run down did this. I suppose "anything is possible" (see above!), but I don't think there is anything in the PCM programming/adaptives that could prevent the engine from starting and running

[MiSaturn]

It had been running the day before it wouldn't start, so I didn't immediately sense compression was the issue... . Vehicle has extremely low miles (for a thirty year old car), so my direction was to chase down some basic no start issues like fuel (in tank and at injectors), spark (good, maybe not great, which lead to the electrical frenzy) and air.

So mindset was age not mileage that led me down the parts path. At this point, unfortunately, I can't easily say what I did could have resolved the issue or not.

The quad code it had, however, has cleared itself at this point. Will take it into the shop to see what they might figure out, then start process of short trips and observation.

It's a pretty nice SL2 that a friend drove and later gave to his mother. He intended to make it his winter sled when she was done with it, so it got new Cooper snow tires and the underside rustproofed.

[fdryer]

Does this SL2 have a throttle body injector (TBI) or plain throttle body with injectors for each cylinder?

[MiSaturn]

MPFI with throttle body air intake.

Maiden voyage was uneventful - after 20 years in an '02 SL with manual, having an automatic seems to make it a bit of a dog. Rotors are bit wobbly, probably from rust build up after sitting for months. Could also be some harshness from the Cooper snowtires, again, something I've haven't had in decades. Otherwise, runs like a 30 year old Saturn.

Known issues include non-working fuel gauge and broken odometer. Read about gears in IP being an issue, will probably send it out to get replaced.

Would like to locate a driver side sun visor, and put in a new head unit to replace the AM/FM stocker.

Still in a bit of culture shock going from the '02 SL, back thirty years to the SL2. First Gen seems very Japanese in execution - some of the trim seems more fussy than it needs to be. Think the 1st Gen exterior was the best - especially like the rear glass treatment and front nose. No contest between OBDI and OBD2 - diagnostics in my '02 were great asset and one of the reasons I was able to keep it on the road for 360,000 miles.

[cgg17]

Originally Posted by fdryer

Does this SL2 have a throttle body injector (TBI) or plain throttle body with injectors for each cylinder?

All DOHC's were multiport fuel injection, only SOHC's from 91-94 utilized the TBI setup.

[fdryer]

^ Thanks. I have to ask as I don't keep up with some things.

Battery disconnect simply resets every pcm or ecm back to factory default settings. These defaults are mainly emissions defaults whether OBD I or II. Battery run down can do the same if voltage drops below a certain level but doesn't alter the basic EFI programs needed to run the engine.

Some things to consider with a very old car left unused for a period of time then returned to road use; battery cable connections/corrosion, all wiring connections corroded, creating intermittent electrical connections resulting in mystery bugs coming and going away, etc.

[MiSaturn]

It had run up to the day it wouldn't, new ignition parts tossed in and could not get it restarted. Then sat for eight months until the opportunity came it work on it again - which, surprisingly, never needed to happen.

Feel fairly confident that it's not directly related to any battery issues, as it cranked over the whole time (until battery was run down). As mentioned, we knew we had fuel and spark, so it really felt like a timing issue (or crank position sensor, which got replaced).

While it's waiting to go to the shop, tackling some cleaning and cosmetic stuff just to make it more pleasant to be in.

Original owner had installed a set of beautiful BBS wheels with gold center sections back in the day, which were replaced with what I assume were stock wheel covers. Enkei makes a similar wheel today, but at $178 each, its a bit more than I'm willing to invest. BBS wheels run $600-800 a piece, which would be completely insane amount to spend on a $500 ride.

[cgg17]

Looks like a really clean example. Leather interior?

[MiSaturn]

Leather? Yep, and very beige-ish! Rear seat nearly unused, driver's seat needs a deep cleaning and needs one of the upper seat bolsters replaced due to wear.

Previous owner added an electric heater to the driver's side seat. Especially nice in a winter car.

Sun visors are shot, and headliner droops in front (my '02 drooped at the back) which seems on par for an SL.

[cgg17]

Originally Posted by MiSaturn

Leather? Yep, and very beige-ish! Rear seat nearly unused, driver's seat needs a deep cleaning and needs one of the upper seat bolsters replaced due to wear.

Previous owner added an electric heater to the driver's side seat. Especially nice in a winter car.

Sun visors are shot, and headliner droops in front (my '02 drooped at the back) which seems on par for an SL.

Very nice, headliner falling is common, easy to replace/reupholster yourself.

The leather always seemed to hold up better than the cloth, at least the integrity of the foam. My newish 94 Sl1 (a former member's) has leather that he installed, and I prefer it over cloth. Both of my 95's have cloth though.

[MiSaturn]

Latest shakedown run of about 45 miles indicated radiator fan might have failed sometime in the past. Seasonal cold weather had masked the issue, did about 20 mile drive and idled for a few minutes and saw needle creeping up past half way mark... .

Did the old "run A/C" to see if fan kicked on (negative) and swapped out fan relay with another known good one to see if it made a difference - nope.

New fan motor ordered - $30 for VDO brand. From what I remember, its a pretty straightforward replacement. Did notice the previous owner had replaced the radiator, which is a plus.

[cgg17]

Originally Posted by MiSaturn

Latest shakedown run of about 45 miles indicated radiator fan might have failed sometime in the past. Seasonal cold weather had masked the issue, did about 20 mile drive and idled for a few minutes and saw needle creeping up past half way mark... .

Did the old "run A/C" to see if fan kicked on (negative) and swapped out fan relay with another known good one to see if it made a difference - nope.

New fan motor ordered - $30 for VDO brand. From what I remember, its a pretty straightforward replacement. Did notice the previous owner had replaced the radiator, which is a plus.

Did the compressor turn on? If it was cold out, PCM will not allow for the AC to be cycled on.

Without cycling the AC, the fan will kick on once the temp gauge (91-94) hits the red zone, or the 3/4 mark (which is high IMO).

[trottida]

Originally Posted by MiSaturn

Latest shakedown run of about 45 miles indicated radiator fan might have failed sometime in the past. Seasonal cold weather had masked the issue, did about 20 mile drive and idled for a few minutes and saw needle creeping up past half way mark... .

Did the old "run A/C" to see if fan kicked on (negative) and swapped out fan relay with another known good one to see if it made a difference - nope.

New fan motor ordered - $30 for VDO brand. From what I remember, its a pretty straightforward replacement. Did notice the previous owner had replaced the radiator, which is a plus.

As cgg17 mentioned the fan did not come on with the A/C button likely due to the ambient temperature being too low. I think it has to be above 40F if I recall before the PCM will allow the A/C to run.

In the 1st Gen S Series the fan will turn on when the coolant temperature reaches 221F. It will cycle off at 212F. From a gauge perspective the operating temperature will be around 1/2, fan on will be past 3/4 and fan off will be somewhere in between. It's best to use a scanner to read the actual temperatures as the gauge calibration is not terribly accurate.

There are 2 temperature sensors (ETCS) in the 1st Gen; one for the PCM and another for the gauge. So it's best to check the one for the PCM to ensure it is working properly even if your temp gauge seems correct. If giving an incorrect signal to the PCM, the PCM will not command the fan on.

The ETCS installed from the factory had a resin tip and they are known to crack. This gives a false reading and sometimes fouls up the wire harness connector. A fouled connector would have to be replaced and should be soldered and shrink tubed into the harness. Crimp connectors are a known failure point on this circuit. The factory switched to a brass tipped ETCS in 2002.

[billr]

More reliable/definitive than fussing with A/C for checking the engine fan is to simply jumper the OBD connector, like for reading "blinky" trouble-codes. That will force the fan on.

Again, I would have applied 12V directly to the fan and ensured it was bad before ordering a new fan motor...

[MiSaturn]

The new/old SL2 went to the shop yesterday to check on its overall health. Didn't have any codes showing, but wanted to see if they could read OBDI "live" and advise of any sketchy readings or recall any previous errors.

They called and said that the vehicle had stored a "Code 74" error which indicated a temperature sensor issue... . And yes, once I checked the actual code for this I realized that the Code 74 should have been reported as Code 14 - temp sensor out of range (high end).

Sounded a little miffed when I passed on getting it replaced - I mentioned that there was a new NTK temp sensor sitting in the glove box waiting for me to put it in.

Also asked to have the headlight aiming checked - was told it was spot on, which is a disappointment since the driver's side lighting is so weak. Had already put a new bulb in, which apparently didn't make a difference.

Hate to complain, but our 2002 SL's headlights were outstanding in range and brightness. People would flash their lights when they were on low beam, and it would really light things up when on high beam.

Last on my list was to get an estimate on getting fuel gauge fixed - $631 to drop tank, replace pump and sending unit. Was another pass - couldn't see dropping over $600 on a $500 car to start with.