Throttle response!!!!!?????

So I average my jeep xj build pretty much done. Just tweeking some final finishing touches.. Well I have a strange problem and I cant trace it down.. It's a alh 10 mm pump 1019 dlc and a malone stage 4 with vnt 17. Immo deleted. Egr delete. Maf delete and some more deletes that I can't think of yet haha. But it starts up and runs great except for the first time you put it in gear and try to pull it dives on its nose and completely cuts the throttle. Let out of the accelerator and get back in it in a few seconds and it's fine and doesn't do it any more until you cycle the key again. No cel.. No nothing just super strange

I think that behavior happens when the ECU is unhappy with the brake pedal switch situation. I initially had them connected backwards and my swap did the same.

One switch should get 12v when the pedal is up, the other should get 12v when the pedal is depressed. You may have them swapped.

I would say that will definitely be a problem because I do t have the brake switch hooked up at all.. Lol

In measuring block 006 of VCDS all pedals need to be "0" - if the brake is on, and by default with nothing connected to it, it is, this will happen.

I have a nifty and inexpensive little box that has a Clutch and Brake inputs that is "conventional style" where at rest there is 0V and pressed there is 12V and the output is the correct output for the 1999.5 and later engines - Clutch/Brake Switch input: 12V=At Rest | 0V = Pressed and Brake Light input: 0V = At Rest, 12V = Pressed

If you don't care about cruise control you can just ground both brake wires. That's how I wired mine up and I don't have any issues.

Frankenyota said:

If you don't care about cruise control you can just ground both brake wires. That's how I wired mine up and I don't have any issues.

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That would present an incorrect signal on a ALH and later engine.

Having a functioning brake circuit is in my opinion a very critical thing. When you press the brake the power is cut and that process is very high in the importance table. Safety #1

I use a DPST relay triggered by the brake light signal for the ECU brake inputs. It toggles the signal when you step on the brakes. Easy.

Rockwell said:

I use a DPST relay triggered by the brake light signal for the ECU brake inputs. It toggles the signal when you step on the brakes. Easy.

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I used to do it that way, but a lot of customers complained about "click click" every time they applied the brakes. N-Channel MOSFET is tiny and quiet!