S'vette

I have a 2016 C7 Z51 C7 with the ECS SC on it and just moved to Hawaii and am in the process of getting the car retuned for the change in elevation and gas type. The tuner is having trouble getting the tune to work right. PSI is low and there seems to be no visible boost leak but there are no smoker machines in Hawaii from what Im told.


The main issue is the commanded timing is not what we are getting and if he makes a change to the timing then the car bogs down and is getting too much fuel. Now he didn't change anything about the fuel when this happens.


The car has only been tuned with HP tuners back at old station and then now here. Could the ECM (ECU?) be acting weird and need replacing?

davepl

I find it very unlikely, but I put a new ECM in my car a couple of weeks ago... they're only about $150 on RockAuto and Amazon.com but need to be initialized by the dealer.

S'vette

Can a tuner initialize them? I thought they would cost more so that's good. How much did the dealer charge to initialize? Thanks.

DOUG @ ECS

A tuner can set them up if they have the correct equipment and are connected to GM global. Most are not.

davepl

I don't know if that's true. I think it takes a full Tech2 bench or whatever they're using at the dealerships these days. In other words, the J-2534 tools that an aftermarket shop would have access to can flash the ECM after initialization, but I don't know if an independent can set the VIN and the initial setup.

The dealer charged me about $220 I think but has to do it in the car (not on the bench). So now I have a fully original ECM in my car with no warranty block (I checked in GM Global Connect) and a spare ECM with my no-AFM tune and so on. But it's in a physical location that's a paint to swap. Wish it was just sitting under the hood like the C4 was!

S'vette

Thanks for all the replies guys. Im really hoping my tuner can pin point the issue in tuning and not have to get the ECM. But he says he has sent it to HP tuners and a friend who does alot of vette tunes and they say it looks pretty good but its not doing well really. Very limited tuners here on the island.

S'vette

Whats really perplexing him and me is that we cant get the commanded timing, its always under by a good bit and when at WOT the car seems to bog down. Got good gas but tuner saw that at WOT too much gas was being given causing it to bog down. Got it fixed some but not good enough. He put new plugs in too.

Read something in HP tuners forum about the KR going over 3* will cause ECM to go to low octane table. Seem like that could be a possible cause?

Blusdacolor

Did you ever find a fix?? This is exactly what I’m having problems with right now. Tuner try’s to get the car to command 18 degrees of timing, but it locks on at 10 and will not adjust.