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View Full Version : Hesitation on about half throttle


akura
10-21-2005, 10:01 PM
I've been trying to figure out this problem for the past week or so. From a stop, applying about 40% throttle would just cause the car to hesitate and rpms to drop until you back off the throttle. My wideband shows the AFR to be really (8-9) rich. At first I thought this to be just a problem with the map on my map ecu, but then I when I tried to set the timing I found some odd things.

I put the jumper on, warmed the car up, etc. When I checked the timing, the car was at about 20 degrees BTDC. As I tried to retard it a bit towards 10 degrees, the car would die. The car would not start at 10 degrees BTDC.

So tell me if this makes sense, idling at 20 degrees BTDC is within the realm of operable. But as I apply throttle, the timing automatically advances it self to the point where it just bogs down. As I let off the throttle it jumps back to around 20 degrees BTDC.

So anyways, I think this is related to the exhaust camshaft being off a tooth one way or the other on the belt. I'm going to try this tomorrow, do you guys think it will cure the problem? Is there any reason the car would idle at 20 degrees rather than 10 degrees besides one of the cams being off?

kbprice
10-22-2005, 04:25 AM
I don't think being off by only one tooth would cause it to stumble that much. I had my adjustable cam gear slip one while racing and it went all the way to 15 degrees. It just loped at idle but never bogged or died.

SuperRunner
12-02-2005, 02:31 AM
Akura, you get this figured out?