Hi,

I just bought a new to me 95 Z28 Automatic (4L60E AFAIK). I'm currently in the process of making the car reliable, and I was wondering what the cause of this may be. Basically if I'm driving like normal it will hit the gears every time, however if I'm giving it some gas, between 2nd and 3rd (I think) the car doesn't shift. It almost feels like it goes out of gear. When I back off for a second or two it then shifts into gear.

Problem observations that may be related, but I don't know:
- There are small fluid leaks all over the place, but I've had the car for 3 days so I haven't figured out exactly where they're coming from (if multiple places), or what the fluid is yet. I went ahead and picked up an oil pan gasket to be sure, but I haven't installed it yet.

- It's a little slow to turnover when the engine is cold, despite "hot" weather. After the car has been running it starts up pretty quickly.

- Strong fuel smell from the exhaust when running.

- Service light comes on and off intermittently.

- ASR light on, ASR button near center console not work


Any advice on what I should do? My goal is to get the car in a reliable/easily maintainable running shape, before I worry about doing anything fun with it. I'm cross posting some of these issues to the appropriate engine forum, but I'll leave what I suspect are the engine problems in here anyway, just in case.

Thanks.

 

Scanning for codes is a good first step. The PCM records fault codes for the 4L60E trans, as well as the engine. Some people find the 95 hard to scan because it has a 16-pin OBD-2 style ALDL connector, but the PCM is OBD-1. You need an OBD-1 scanner with a 12-pin -> 16-pin adapter. Or shbox.com will show you how to use jumpers to hook a 12-pin OBD-1 cable to your 16-pin connector. Do not attempt to use an Innova scanner - several models will not work correctly.

Better than a hardware scanner, go to the "Computer Diagnostics...." Forum and look at the "sticky" thread for a free download of Scan9495 software. You will need to buy a cable. The author of the software is a member here and actively responds to questions and problems. I (and a couple others) can go through the data log the software produces, and help you identify the source of problems.

 

Alright that sounds great. I'll post back in here after I get the results; thanks.

 

OK, it took awhile, but I finally got it setup. I had a transmission fluid and filter change done, and it's shifting much better. However I still ran the program.

Here are the logs I ended up with:
https://www.dropbox.com/sh/2hulr78du...I1BxyQLKa?dl=0

Transmission is the 18kb log.

Now I didn't drive around with this on or anything, so idle only readings. However if it matters the battery hasn't been disconnected since I've bought it.

 

I responded to your thread in the "LT1 Based Engine Tech" forum.

With regard to the transmission, I don't see any transmission codes, so you need to drive it for that as well. The trans data log would be more meaningful, but I'm not an auto trans expert, so my analysis would be very limited.