What tuning can be done on a 964 without a Bosch Hammer?

I currently own a 1993 Dodge Stealth RT/TT and a 1996 Nissan 300ZX 2+2 (commuter car). The Stealth is ODB I, and the 300ZX is ODB II. My question is, how limited is the work a home mechanic do on a 964 without a Bosch Hammer?

On the Stealth, almost ALL functions on the can be done either by a dealer supplied diagnostic tool ($$$) OR they can be done by me (at least about 90% of them) by jumpering some connector wires and then using a VOM to read diagnostic codes.

The 300ZX, on the other hand, is severely limited...there are a FEW things a home mechanic can do with a VOM (this isn't true for all 300ZX's..in fact it may be limited only to the 1996 model), or you must buy a factory or aftermarket analyzer, and both of them are fairly pricey items (the cheapest tool I've found for the 300ZX is about $1000.00).

How reliant are the 964's on the Bosch Hammer for analysis of the electronics of the car? Is there a way to circumvent the apparent reliance on this tool (like using a VOM and jumpering some wires) or do you need to go to someone with the "Hammer" to get an analysis done? How much is this "Hammer" anyway? Are there third party alternatives?

I'm NOT an expert on 964s or the Bosche Hammer, so please, correct me if I'm wrong on any of this.

Thanks in advance,

Bill Wagner

I priced the Bosch system tester last year. By the time you have the hammer, program, and cable it came to over $8,000. I have found the factory manual to be invaluable, in addition to all the hammer procedures it also has data on the all the sensor inputs in standard values; ohms,volts etc. Also shows signal wave-forms for the scope-able signals. Using the manual I wasw able after some time to track down a cold start problem on my C4.
The Haynes diagnostic book gives a procedure for reading the codes from the eng computer (89-94) but I have not been able to make this work on my car.

Bob Ellis
90 C4

Bob:

Would you say that the manuals are written under the assumption that some mechanics don't have access to the "Hammer", and that the majority of tests can be circumvented without using it?

Thanks,

Bill Wagner

The ability to read the codes is certainly the most valuable aspect of the tester. Without this you have to independantly test every input sensor. The manual is written around the tester and the additional information is supplementary to the tester. The one thing I haven't been able to achieve, without the tester, is figuring how to build a test harness to operate the solenoids on the 4WD system to allow the system fluid to be changed.

Robert, I have some more questions for you:

1. Do you know if the 964 is classified as ODB I or ODB II (or neither)?

2. You mentioned a Haynes manual. What's the title of it? What types of diagnostics does it claim it can provide you with?


Thanks,

Bill Wagner

1) ODB nothing as far as I could tell.

2) The Haynes techbook is titled Automotive Computer Codes. ISBN 56392 232 0

I found a copy at my local Autozone, cost was about $15 if I remember. It is a good general resource and covers Acuras through Volvos. There are also good chapters on general trouble-shooting.

Bob
90 C4