breaks up @ 3000 rpm's

[saabfan9]

hey guys took the car out for a decent ride when i'm over 3000-3100 rpm's seems to start breaking up. idle seems good. anything i should check or is there an adjustment in the fi system?

[SwedeSport]

CIS? or carbs.

[DrewP]

I think his may still have the D-Jetronic electronic system in it.

Did it drive when you first got it? I can't remember if you bought it running. Did it do this before, or is this a new thing since you had it apart for paint?

[Crazyswede]

I think his may still have the D-Jetronic electronic system in it.

Did it drive when you first got it? I can't remember if you bought it running. Did it do this before, or is this a new thing since you had it apart for paint?

if its D jet and you do not care about staying stock...you could switch over to LH reasonably easily.

[saabfan9]

is the d jet a bad system?..no it was like this before but at that time i drove it once from transport depot to home..tried to set timing but bottomed out on the adjustment and backfires (through throttle body) bad so i set it by ear now no backfires ..cruising at 50-55 is ok but any accel or over 55 mph is not so good

[saabfan9]

sorry it has 4 separate fuel injectors at the intake ports...in todays world would be called port fuel injection i guess

[DrewP]

Yeah, that's D-Jet, it was a very odd, very early, all-analog system that Bosch rolled out and very few car companies used it. Saab only used it for 2 years, then went to CIS mechanical fuel injection (for the US market at least).

The reason to switch is because it can be very difficult to get spare parts, and it can be difficult to diagnose since the setup has no onboard diagnostic ability.

I actually can't get my white 99 to start because I haven't had the time to make sure all the D-jet parts are sorted out.

Do you have a copy of the factory manual for the fuel injection system? It has some fault tracing steps in it.

[saabfan9]

found some stuff about the system i'll start the diag...just if someone else out there could use it here are a few sites i came accross... http://www.vclassics.com/archive/efi.htm ... http://www.scribd.com/doc/7303245/D-Jetronic

[Jordan]

Here is the SAAB factory manual that Drew was referencing:
http://saabrally.com/downloads/SAAB_99_D-Jetronic.pdf

[saabfan9]

i have a pertronix electronic conversion in my car i have run these on all of my old cars in the past and never had a problem but i see the d-jet uses a referance from the distributor just wondering if anyone else runs a pertronix

[saabfan9]

NICE ..thank you guys....i've read about the main ground, mine bolts to an aluminum trans case i would not think this would be a proper grounding point..is this just where they are or has mine been re-located at some point (just dont want to over look the simple things)

[DrewP]

The D-Jet dizzys have two triggers in them, one for ignition (was originally points, yours is now Pertronix) that's on top, and a magnetic trigger below the mounting plate for the breaker points, that's what that wide 4-pin connector on the side of the distributor goes to.

Thanks for referencing that D-Jet manual Jordan.

[saabfan9]

ok silly me for using common sense...so i set the engine at "0" tdc #1 found the dist was out more than i could adjust so i pulled the dist and moved it 1 tooth able to get the dist to align with rotor with room to make timing adjustments started fairly easy but runs like crap and dies out.. when it was running the timing was good at 8-10 (spec range) crank the dist to around 20-25 degrees and the idle is better (barely) but still dies out ..before i had to fuck with it at least the car ran...should i ignore the books and common sense?...help before i fuck it up more

[Jordan]

Does the distributor have a vacuum advance? If so you should pull the line going to it while setting the timing and when it is plugged back in it should return to 15-20. Also, mechanical advance goes up at RPM so you need to keep the idle (and low) steady to accurately set it.

[saabfan9]

ya tried it like that... i went out this morning and again set it by ear and seems to start good (vs. that slow out-of-time crank) and runs better but i know if i were to put the timing light on it she would not be anywhere near that 8-10 (no vac/800 rpm)...i just wanted to start with the basics and i thought i would set timing before i fucked with any of the d-jet stuff