Pinging .... Resistor >>>> Heat question
 

N. California is having very unusually warm temps .... mid 80's .... The 87 190e 2.3 has started pinging. I notice it most during the warmest part of the day, so obviously there is some relationship.

I replaced the "infamous" power resister to see if this helps.

Is it normal for an engine to ping more when it is hotter out?

haasman

Depending on what octane you are running it could, higher the octane, less problem you should have..

Inlet air temperature is a BIG factor in the detonation equation. The higher the inlet air temp, the higher the propensity to detonate. In the winter I can run 87 PON in my M103, but not in the summer!

Most FI engines have a cold air induction system with a duct to the area in front of the radiator to pick up cool, ambient temperature air. This both reduces detonation tendency and increases power relative to aspirating heated, under hood air. Make sure your cold air duct is intact.

The recommendation for my erstwhile '84 2.3 was 87 PON but I believe your '87 2.3 is 91 PON, same as the M103 six-cylinders.

Duke

Thanks for the replies. I thought the efficiency of hotter less air would contribute but I am surprised at only 80 degrees how pronouced the pinging is.

I am running 91 octane. I will double-check the cold air duct, good thought.

I didn't remember the pinging last summer .... weird.

haasman

I would look at new pinging in warmish weather as a sign something has changed. Check timing, plugged EGR, open vacuum hose, etc.

Steve

Steve

My thoughts exactly. I haven't check the timing on the 190 but I should. Is it straight forward .... any tips would be appreciated.

haasman