996 to 986 Instrument Cluster question

[obthomas]

Has anyone discovered the eeprom re-programming to make the gas gauge work correctly with a 2002-2005 996 c4 gauge transplant? The problem is the tank is empty when the gauge reads 1/4 tank.

I understand I may be able to get the dealer to re-code the fuel tank type or I may be able to hack the sender, but I thought I would check to see if anyone has made progress with the eeprom.

[Sikest]

I have done two of these any never had that issue. I just finished my last swap last week. 2003 Boxster S with a 2002 911 C4 Cab cluster. Gauge is spot on.

Not sure that helps but I have not had that issue.

[JFP in PA]

These fuel level gauges are programable with everything from a PST II to the Durametric system; you simply need to follow the recalibration procedure in the service manual.

[obthomas]

Originally Posted by JFP in PA

These fuel level gauges are programable with everything from a PST II to the Durametric system; you simply need to follow the recalibration procedure in the service manual.

JFP Thanks for your response. I have come to have great confidence in your advice.

A little more help please. I have the Enthusiast Durametric and best I can tell neither it or the professional version will calibrate the fuel tank. Am I wrong?

This is my hobby car and I dread going to the dealer and explain that I have cobbled the cluster and that I want him to PIWIS it as a 996 and calibrate my fuel. My sense is the dealer will not want to mess with me. I may try a few other thing first.

Anyone?....Particlewave? ..Does anyone know the eeprom bits in the newer blue grey and green connector cluster for a 986 to turn on the oil pressure and voltmeter? or alternately, does anyone know the eeprom bits to go from 20 gal to 16 gal fuel in the 996 blue grey green cluster?

Another possibility, at this point my sending unit span is from 12 ohms full to 300 ohms empty. I wonder if I add a potentiometer and adjust the sending unit to half a tank would that work? I'm not sure because I think my cluster is set to do that final 1/4 calculation so my OBC would be wrong.

Finally, I can just go on living and knowing that I am out of gas a 1/4 tank. None of this is super important on a hobby car, just fun.:dance:

[JFP in PA]

The Enthusiast version will not do it to my knowledge, you would need to check with Durametric on that. The 996 cluster was designed to be used with two different gas tanks, the regular one used on the two wheel drive cars, and a saddle shaped one used on the four wheel drive cars. As the result, it had to be calibrated to the car by draining the tank completely, then refilling it to a specific volume of fuel; 12 liters for a two wheel drive, 28 liters for a four wheel drive car, then running the gauge calibration on the scan tool.

As the cluster's electronics for the gauge are somewhat different, I do not know if any data can be lifted from on and transferred to the other, but I do know that the factory calibration system does work.

[obthomas]

Originally Posted by JFP in PA

The Enthusiast version will not do it to my knowledge, you would need to check with Durametric on that. The 996 cluster was designed to be used with two different gas tanks, the regular one used on the two wheel drive cars, and a saddle shaped one used on the four wheel drive cars. As the result, it had to be calibrated to the car by draining the tank completely, then refilling it to a specific volume of fuel; 12 liters for a two wheel drive, 28 liters for a four wheel drive car, then running the gauge calibration on the scan tool.

As the cluster's electronics for the gauge are somewhat different, I do not know if any data can be lifted from on and transferred to the other, but I do know that the factory calibration system does work.

Thanks again. I believe you are exactly right. Ugh dealership. Last resort, will get back to you if I discover a work around or hack.

[Bill Ladd]

@obthomas - Prior to purchasing my Durametric, I rented one off eBay to set up my cruise control.

Think it was around fifty bucks of so. Easy peezy.

[obthomas]

Bill Ladd If you ever want to turn off you cruise control I will rent you my Durametric for $50. Easy Peasy.

[Bill Ladd]

What?

I already bought one.

I’m telling you that you can rent a full-function durametric from eBay to calibrate your gauge rather than go to the dealer.

[obthomas]

Bill Ladd

I just talked to Owen at Durametric. The Professional does not calibrate fuel on a 986 and in fact Owen says that the professional does not do any more then the enthusiast for a 986. So for a 986 the enthusiast version is as good as it gets. I did not know this. Now I do.

[Bill Ladd]

Well crap. Just going off what JFP said. Was excited to find a solution for you to keep from paying those dealer rates.

Ah well.

[obthomas]

I found an Indy that is willing to work with me and has the PIWIS. Waiting for an email with an estimate.

[JFP in PA]

Originally Posted by obthomas

Bill Ladd

I just talked to Owen at Durametric. The Professional does not calibrate fuel on a 986 and in fact Owen says that the professional does not do any more then the enthusiast for a 986. So for a 986 the enthusiast version is as good as it gets. I did not know this. Now I do.

Interesting, but not sure that is correct; their own site says you cannot activate the cruise control on a 986 with the Enthusiast, but rather need the Pro.......unless something has changed.

[Bill Ladd]

If I get a chance, I will hook up my Durametric pro and see if it gives me option to calibrate fuel gauge.

I'm crazy busy lately, so it will be a few days if I get that chance.

[particlewave]

The only difference between the Enthusiast and Pro versions has always been the number of VINs that can be stored (3 vs unlimited) and neither can do fuel gauge.

[obthomas]

Originally Posted by obthomas

I found an Indy that is willing to work with me and has the PIWIS. Waiting for an email with an estimate.

Got a quote to calibrate my fuel gauge .
490 dollars

[obthomas]

Originally Posted by JFP in PA

Interesting, but not sure that is correct; their own site says you cannot activate the cruise control on a 986 with the Enthusiast, but rather need the Pro.......unless something has changed.

Something must have changed. My durametric enthusiast 986 cluster activations or coding has both onboard computer and cruise control send activations

[obthomas]

A new approach......Is there anybody out there that has done this 996 blue grey green connector cluster into a 986 and everything works including the fuel gauge calibration that can share a download of their eprom.

[ike84]

This may help, is from the 996 factory repair manual. A known issue with fuel level readings on empty tanks after a battery disconnect.

Sent from my POCOPHONE F1 using Tapatalk

[KevinH1990]

Originally Posted by obthomas

A new approach......Is there anybody out there that has done this 996 blue grey green connector cluster into a 986 and everything works including the fuel gauge calibration that can share a download of their eprom.

What is the year of your car? (It has been a while since I installed my 996 cluster and I have forgotten the colors of my connectors.). If you have the LCD-type cluster I have the EPROM dumps from both the 986 and 996 clusters I used in my 2000. The files are stored on a hard drive and I should be able to find them this weekend.

By a process of elimination you may be able to determine which line of code controls the fuel gauge and update the offending bits.

This post Carrera Gauge Swap shows the code for the old style cluster. Lines 1 through 3 of the code include the odometer reading and the VIN. One of the remaining lines probably has the fuel tank type encoded.