naturally aspirated? i figure it is usually run with the lowest octane fuel available?

i've been having a similar sounding problem with the suburban, and it was rather worrying me before i got the smog test done yesterday.

i ran the tank to almost empty the night before, then put in about 7 gallons of 91 octane.

no more miss, no more stumble, and it is starting to feel more like the 350ci v8 that it is, not a v6.

try some better fuel, or some fuel treatment or something. that might be all the problem is, low octane.

 

oh, btw, the suburban passed smog easily with the 91 octane and a good, hot exhaust. it hasnt stumbled or missed since i stopped running it on 87 octane fuel.

 

Techron is smoothing up my '91 quite nicely... worth a shot at <$10

 

Take it back to andrews.

 

This was something I specifically directed them not to deal with. I also really don't have time before I leave to go up there, deal with them, and come back.

I put a tank of 92 octane in it, so that's not it.

I'll try the Techron - I have an extra bottle in the garage anyway. Easy enough to try.

The n/a's use a 3 bar FPR, right? I may well pull the 3 bar FPR off my convertible (in winter storage) and swap it out to see.

 

We had a similar problem with our '92 900S and it turned out to be the FPR so you might want to give that a shot.

 

I am inclined to think it is fueling related as well. Other than the basics which it seems you have already covered it would take some more involved troubleshooting to resolve. Which it seems you do not have time for at this point. Keep us posted on how it goes. Good luck. Be safe.

 

I don't think it will be a bad FPR. Pull the vac line off the FPR and give it a sniff, see if that does anything.

When will you be home tonight greg? I drive past your road while driving on 50th street every night on the way home, I could stop and take a quick look/drive around 5:30 if you're there.

PS - How is the timing?

PPS - and the plugs?

 

Good call on the vac lines. I still have some bulk tubing left over from when I did mine if it's needed. My line to the FPR was so cracked and brittle it literally spewed on me in powder form! It was like charcoal...

 

If the front mount is bad it culd be the dist. cap hitting the hood causing it. Try accelerating slowley and see if it does it. Otherwise the Techron works very well for dirty injecters

 

This makes sense, because it happens right when you step on the gas, when you need torque to start out -- which I presume is also when the motor would be twisting the most.

It's completely normal at idle.

 

Check the throttle position sensor

 

Gee jack, there's an idea, and it's soooo easy to check the alignment of the sensor, that you'd be a fool not to!

If the sensor is out of alignment, the ECU may be thinking that the throttle closed/at idle when it is actually open, which effs up the fueling until it does hit the "open" point on the sensor. Just a possibility. It should click if you open the throttle even the smallest of trifles.

 

Pull the dist. cap off, and if it is hitting the hood there will be noticable grinding marks on the top side of the cap.

 

I will stop by Greg's tonight and I will check this out.

 

JK stopped by.

Well, it's not hitting the hood -- distributor cap is fine.

FPR seems good, too - no gas smell in the vacuum line to the FPR.

Next guess - spark plugs and wires.

 

I once had a set of bougiecord plug wires crossfire. Whenever you popped the hood at night you could see them... Needless to say i replaced them! Something to think about...

 

you say the previous owner replaced the plugs, maybe 10k miles ago?

did he use the correct NGK plugs, or the $8/piece alternatives that really dont work so well?

also, check the gap.

 

There is a set of "known good" Bougicord cables headed to you Greg.

 

Cool. Many many thanks.

 

a junk yard friend and I were just discussing this (he has a 90-900-S) it apparently has this same sort of skip and it "catches" and gets going again around 2000 RPM's, but his also had a tenancy to shut off when you shifted sometimes. Well we were talking and he's replaced just about everything, all the way down to the ignition amp. and the EZK box... Though he had NOT replaced the CPS, which was going to be my suggestion in this case as well. my 89 900-S was having occasional odd ignition related faults, where the ignition was shutting down and popping back on (only when wet though). I did not replace the crack sensor, (too expensive and hard to replace on a C-900) I simply replaced the distributor with an old style unit from a 900-S with a hall sensor, made an adapter to plug it into where the crank sensor used to plug in, and bam, no more crank sensor.

 

yeah unfortunately with the fixed timing there is very little igntion related that can go wrong short of the dreaded crank sensor. make sure you check that the plugs are properly gapped, even if they were just replaced, Delorean and i learned this the hard way, trying everything else before gapping the plugs and solving the problem entirely. how 'bout the AMM? TPS sounds like a possible one too, there just isnt really too much that could cause a low RPM only issue.

Paul

 

Also, with the 2.1 cars, keep a close eye on the coolant level. It's a good engine but they are more prone to coolant loss issues than the 2.0 motors, and you do NOT want to overheat one, or it will be headgasket time for sure.

 

Sorry Jack, but this is a 2.1l car, so it has a completely different TPS, its a potentiometer rather than a series of switches, so the only way to test it is with a multimeter, and the specs in the bentley manual. also theres no adjustment with that TPS, so its either good or bad, and if its bad ya throw it away and replace it.

Paul

 

Ah, I see

I guess that's why people with turbo cars need the 2.1L TPS, never occurred to me to ask why :lol:

 

yep, all LH 2.4.2 cars use the same TPS as the T5 cars and do not have all that funny internal gadgetry. Again, like the distributor the TPS on LH 2.4.2 cars is not adjustable, and it's never needed. The same is true for the airflow meters. All this stuff gets calibrated automatically every time you start the car so there is no fussing around needed. LH 2.4.2 uses a lot of the same parts as T5 cars, even the wire diagrams look similar. I think when saab made the T5 system, LH 2.4.2 was probably their basic starting point

 

I think when saab made the T5 system, LH 2.4.2 was probably their basic starting point

I'm sure that is correct since T5.2 is very very similar in many ways to LH2.4.2, and then T5.5 is what the finally settled on.

 

Oh, Li'l Red, I can't wait to meet you....

 

i had a feeling this was that one.....

 

New spark plug wires did the trick. No more miss.

Thanks to JK and Palmer for their contributions.

 

New spark plug wires did the trick. No more miss.

Thanks to JK and Palmer for their contributions.

I think that is beer/food worthy to be sure!

 

Boo-yeah. It's always the simple stuff.

So you will miss the LeMons meeting then, Greg?

 

Boo-yeah. It's always the simple stuff.

So you will miss the LeMons meeting then, Greg?

Yeah, I forget about the Detroit trip when I mentioned the LeMons meeting.

My only contribution would have been to cheer you on and consume beverages, anyway.

 

The car drives pretty nice! I like those 2.1 liters.

I few odd things, there is something funky with the shifter (feels much like champs car), its not the trans, its the housing, and it makes finding reverse kinda odd - nothing major.

Also, the steering column is all fucker'd up. Its loose right around the base of the wheel, but its not the wheel, its the shaft. Again, not major, probably an easy fix, just a bit annoying.

 

Also, the steering column is all fucker'd up. Its loose right around the base of the wheel, but its not the wheel, its the shaft. Again, not major, probably an easy fix, just a bit annoying.

The car was stolen and then recovered by the previous owner, which accounts for the damage to the steering column. This is also why there's a different key for the ignition than the doors/hatch (and may account for the shifter weirdness).

It was apparently used as a mobile crash pad for a homeless person during the month it was stolen, before it was recovered.

And yes, the car has been christened Lil Red. And I have christened the Resurrection SPG as Big Red.

Big Red is loaning Lil Red his spare wheels and the SaabSavior skid plate for the trip to Labrador.

 

It's always the shaft.

 

yeah, steering shaft problems are very common at this point. the press fitting tends to wear out and the entire wheel will slide in and out or side to side if it's a problem with the upper section. If it's a steering link problem, the steering tends to bind around turns and the car feels like it has a bad steering rack. gotta remember to center it up around turns manually or it might just keep turning all on it's own :lol: my 270K SPG has bad both, and a bad rack too, so I know all about steering issues...

and yeah, the 2.1 cars go pretty good when everything is right with them. I am pretty sure they'd beat a turbo up to 60 with the right driving method after that there would be no contest but they are fairly fun around town.