Hey Guys,

I was driving home today and started hearing this ping noise - like when you put bad gas in your car. When I started going up a hill and needed to accelerate I noticed more. The car runs fine - but did seem to lose power going up the hill.

Cheap gas? the timing slipped so its overadvanced now? I use premium gas so I can run the most advance I can-32 degrees BTDC @3500rpms

Geoff

I thought it may be timing. I use 91 octane gas so i didnt think it was the gas....

Pinging can be caused by several things in combination - too much ignition advance, too lean fuel mixture, and temperature of the air (hot air = more ping).
If you can verify that the timing is correct , and that the advance isn't stuck or sticky, (and assuming your gas isn't bad) I'd suspect that something is causing you to run lean such as a clogged injector(s), clogged fuel filter, or dying fuel pump.

-Ben M.

What does advancing the timing do? Does it give you more power at the bottom end, middle or top end? I've heard what it was but (with the onset of grey-ness... I forget
bruce

Let me put it this way "Lower-than-optimal timing advance will result in less power". More is only better if you are using less than what is optimal. The question is what is optimal timing advance? For a D-jet type-IV that lives in a warm climate I'm going to have to say 27 degrees BTDC. I've tried to get more max advance but can't without richening the mixture beyond the point of max power (to prevent pinging). I know some carb guys are running more advance, but I suspect they are also running pretty rich. (somebody jump in if you've had different experience)

On my PEFI/ignition engine I am running more low-rpm advance than stock, but it still maxes out at 27 BTDC at ~3,000rpm. This gives more torque off-idle, but probably raises emissions as well.
-Ben M.

I have my 1.7 D-Jet timed at 27 BTDC. After re-doing all the vacuum hoses, new Pertronic ignition and different injectors it's running stronger than hell. I've been temped to mess w/ the timing to see what happens. I've also found since I've done all this it runs cooler.
When I first got the car I noticed when I shut it off and stood along side at the engine bay there would be an enormous amount of heat coming from under the car. This worried me. Hope it never got too hot to screw somthing up... so far so good