Quote:
Originally Posted by zr1man@yahoo.ca
I just bought a 1991 corvette zr1 and i dont find any difference when i switch from normal to power mode. in normal mode the car drives fine. when i switch to power mode, the light comes on. car still feels like 210 hp and when i accelerate heavy, the car pulsates and vibrates. when i let off and drive normal, the pulsation goes away.
im thinking its the secondary injectors that may be the problem as i continue to read in the other posts.
I would like to be sure before i invest in them. Also, if it is the injectors, is there anybody you can recommend with a decent price? Im from Canada if that makes a difference. Maybe the local parts shop can order from a major supplier.
sorry, one last thing... any advice or tricks to do an oil change? and is it true the zr1 takes 12 litres?
thanks in advance!  |
Based on the symptoms you describe I would start by looking for a problem in the secondary throttles vacuum system.
I had a similar problem with my 1994 when I bought it.
The first easy check is when you turn the ignition key to ON without starting the car, do you hear the Secondary Vacuum Pump run for a few seconds and then turn off? The pump is located just forward of the coolant overflow bottle, near the pass side headlight.
If the pump doesn't run at all, it needs to be replaced before you can do any other analysis.
If the pump runs-stops-runs-stops-etc, then you have found that there is a vacuum leak that you will need to fix before you do any other analysis of the injectors.
Another quick way to test the vacuum pump is to find the thin plastic vacuum tubing that runs from the vacuum pump to the engine. Right near the alternator, there is a connection that you can separate. With the ignition key on, pull that vacuum line connection apart and by putting your thumb over the end of the tubing coming from the pump you can easily check its operation.
Post up and let us know if you vacuum pump is working.
Jim