cash's90
Well-known member
This is my second post since I bought my '90 coupe two weeks ago.
Jackstands;
I've never owned a corvette before but I've worked on and under many older (mainly 70's or earlier) British sportscars. I always use jackstands when working under cars. At the rear end, I typically position my floor jack under the differential and then place the jackstands under the rear axle shafts or spring mounting points. At the front, I typically position my jack under the front cross member and place the jackstands under the lower A arm mounting points.
What is the best method for my '90 C4? I'm concerned that by using the jacking points and putting the jackstands under each point, I'll place abnormal stress on the frame.
Misfire;
I've read many of the posts on this forum that discuss rough idle and acceleration probems but have not found any that sound specifically like my problem.
The PO said he only drove the car once a week for several months so I convinced myself that the following problems were related to a lack of use.
My car starts easily and runs smoothly, under normal acceleration, until it is completely warmed up. Once warmed up, while sitting at idle with the (newly repaired and very effective) airconditioning on, it starts to miss (heavy misfire) sporadically. The misfire becomes more frequent the longer the car idles. If I accelerate normally from rest between misfires the car runs OK. If I accelerate normally from rest during a series of misfires, the car tends to stumble. It almost always stumbles under hard acceleration (we used to call the way the car acts under heavy acceleration "crapping out").
I've replaced the distributor cap & coil. The ignition module tested OK at AutoZone. The plug wires appear OK. I've added injector cleaner to my fuel , I 'm going to replace the fuel filter (hence the need to place the car on jackstands) and clean the TPI air intake with carb cleaner per the manual.
The water and oil temperature both stay at about the lower third of their range during the mid 80 degree temperatures we've enjoyed the last couple of weeks.
I'll appreciate any and all suggestions.
Jackstands;
I've never owned a corvette before but I've worked on and under many older (mainly 70's or earlier) British sportscars. I always use jackstands when working under cars. At the rear end, I typically position my floor jack under the differential and then place the jackstands under the rear axle shafts or spring mounting points. At the front, I typically position my jack under the front cross member and place the jackstands under the lower A arm mounting points.
What is the best method for my '90 C4? I'm concerned that by using the jacking points and putting the jackstands under each point, I'll place abnormal stress on the frame.
Misfire;
I've read many of the posts on this forum that discuss rough idle and acceleration probems but have not found any that sound specifically like my problem.
The PO said he only drove the car once a week for several months so I convinced myself that the following problems were related to a lack of use.
My car starts easily and runs smoothly, under normal acceleration, until it is completely warmed up. Once warmed up, while sitting at idle with the (newly repaired and very effective) airconditioning on, it starts to miss (heavy misfire) sporadically. The misfire becomes more frequent the longer the car idles. If I accelerate normally from rest between misfires the car runs OK. If I accelerate normally from rest during a series of misfires, the car tends to stumble. It almost always stumbles under hard acceleration (we used to call the way the car acts under heavy acceleration "crapping out").
I've replaced the distributor cap & coil. The ignition module tested OK at AutoZone. The plug wires appear OK. I've added injector cleaner to my fuel , I 'm going to replace the fuel filter (hence the need to place the car on jackstands) and clean the TPI air intake with carb cleaner per the manual.
The water and oil temperature both stay at about the lower third of their range during the mid 80 degree temperatures we've enjoyed the last couple of weeks.
I'll appreciate any and all suggestions.