breaks up @ 3000 rpm's

[saabfan9]

checked the trans fluid it was full i went down to clean some things up..possibly coming from the dist and running down but i couldn't tell you cause i dicked around with the distributor again had a few good backfires never got the car to start again (poss. flooded) had to call it a night this little boy was getting sleepy and frustrated

[saabfan9]

ok does not make sense to me but where the car runs best the rotor is between #1 & 3 at top dead center mechanical...any ideas?

[DrewP]

Did you pull the rotor off and make sure that the indexing notch is actually slotted into the top of the distributor shaft, and isn't broken off or anything?

[saabfan9]

well i am assuming that my distributor/idler gear is out of time keeping me from properly setting the ignition timing (valve timing is dead on) since this will require the engine coming out is there anything else i should address while it's out also is there any place to get a full teardown kit?....also does that sound correct about the idler gear being out of time?

[Jordan]

the idler gear and distributor gear are not indexed...so you can just pull the distributor off and rotate the gear if its not not lining up properly in the body. Unless I'm confused about what you're saying.

No need to pull the engine unless the lay shaft gears are stripped.

[saabfan9]

my distributor reads halfway between #1 & 3 on the cap which would be something like 100 degrees atdc but with the car like this a timing light shows the car at 30 btdc (i wish i could show this in pics not sure if i'm describing correctly)...i'm having a real hard time getting it set up properly luckily i have not messed with anything else...with the timing light reading 8 the car runs like shit (if at all) she seems happiest at the 30 mark but then i'm also out of room for adjustment i've already moved the dist 1 tooth

[saabfan9]

ok car ride into work...if i keep it at 3100-3200 rpm's and about 52-53 mph she runs good anything past that and it bucks and breaks up under load...in the garage you can rev it up clean in neutral but under a load totally different story

[DougM]

I don't know anything about pertronix to comment if that is the problem. I find it hard to believe that all the timing adjustments you have played with, that your car still has a problem, so I would tend to believe that is not your problem - it should run great at 13btdc unless...is the chain tight? A loose chain/bad tensioner could cause the timing to change at higher revs. My first experience with a d-jet car 25 years ago had this problem - would not go over 50 mph downhill with a tail wind. If the chain is tight, my next guess would be the throttle position switch defective or out of adjustment. Here's a page to set it correctly



Is the fuel pressure at 31psi? I'd also go out on a limb and offer the use of the Bosch D-jet tester, but I'd be reluctant to ship it. It's priceless to me, and it works, so I'd be afraid to put it in the mail and take my chances it wouldn't get damaged. I'm only 6 hours away if you felt like taking a drive.

[DougM]

I'm also going to admit that I've owned at least one d-jet 99 since 1986, and I can name on one hand the problems I've had with the system, so there's not a lot of experience troubleshooting. Most of the parts on my 73 are the same ones from the car I bought in '86.

One was the timing chain tensioner problem I mentioned, then I had a too high a fuel pressure fouling out the plugs. In 2003 I actually was stumped at a no start condition and I had to use the d-jet tester(which I bought in 1990 and never used before) - after going through the complete test procedure, it found a bad ground at the group of wires at the bottom of the battery tray. More recently was backfiring and running on two cylinders coming back from Carlisle - ignition points somehow came out of adjustment and it would not run well below 3000 rpms. The only other problem I ever had was an air hose came off the auxiliary air regulator and the rpms shot up to 3000 at idle.

I guess I've been lucky.

[DougM]

If you do investigate the TPS, you could pop the cover off and inspect the terminals - make sure none of the arms are bent or contacts are burnt.



For reference you could try setting it where mine is - my car runs great at all rpms. Sorry I couldn't get a better picture, but it's tough getting a good angle at it.

[saabfan9]

doug thank you for all the info ..i'll go out and do some tests today

[saabfan9]

i did the test between 17 & 47 and i had nothing even took the cover off to test below the connector still nothing so i am assuming my throttle sensor is bad (at least it's a start)...does anyone know where i can get one? anyone have a known good used one ? are they the same on the k-jet cars? is this a common failure?...sorry for all the questions guys

[DougM]

I was wrong about fuel pressure if you decide to check it - 28psi is the correct number. 31 would probably foul out your plugs.

I know I have a brand new TPS somewhere, which I paid a pretty penny for. I think I also have a few I bought off ebay which are used, and are of unknown condition. I have to work late tonight, so not sure when I'll have a chance to locate what I have.

K-jet cars didn't use such a device.

Common failure? Well, the electronic part could potentially be almost 40 years old.

[Crazyswede]

I was wrong about fuel pressure if you decide to check it - 28psi is the correct number. 31 would probably foul out your plugs.

I know I have a brand new TPS somewhere, which I paid a pretty penny for. I think I also have a few I bought off ebay which are used, and are of unknown condition. I have to work late tonight, so not sure when I'll have a chance to locate what I have.

K-jet cars didn't use such a device.

Common failure? Well, the electronic part could potentially be almost 40 years old.

I have a D jet manifold at home which has the TPS attached to it still.

[DougM]

I'm sure there are a few here who parted d-jet cars with no intention of ever running d-jet in their future. I still have a d-jet car, so getting rid of good fuel injection parts you can't buy anymore could be counter-productive for me. Back when I had lots of money, hopping in the 900 to drive 9 hours to CT for parts was not a problem - I did that a few times, or the time I drove 18 hours round trip to PA for some 99 doors, or the over night excursion to Harper's Ferry for free 99 parts in an old schoolhouse. Those were the good ole days.

I did happen to find a very nice used TPS this morning after I posted, but if you can get someone to donate one, you might be better off.