Rough idle / stalling after remote start install

I recently installed a command start system in an 04 I think Pontiac Montana. Using the Blade module the install went well. Now a week later the customer is complaining of rough idle and stalling. I found an obscure post on some forum about the tach wire being run too close to some of the ignition stuff so I relocated it but it seems to not have helped at all. The engine light is on but I couldn't check what the code was due to my tool acting up. It is entirely possible that the issue is unrelated as it only seems to happen when engine is very warm. However I need to cover my bases before I tell him it isn't my problem. Any thoughts?

Did you use a injector wire as your tach signal?

You may have missed one of the IGN/ACC wires.

tach signal I used the white wire at the ignition control module at back of engine. And I do have both ignition wires as the remote start works fine. The car idles rough regardless

2 X 12V+ supply 1 X starter 1 X IGN 2 X ACC. All done?

Does this rough idle happen all the time or just with the RS? If it's all the time, logically not your problem. Look to 02 sensor or ECU where it controls the mixture. Initially, disconnect the battery for 20 minutes, reconnect then see.

howie ll wrote: 2 X 12V+ supply 1 X starter 1 X IGN 2 X ACC. All done?

ummm 1 x 12v red 1 x starter yellow 2 x IGN pink white 1 x ACC orange is what I have. And again the remote start function works fine. So I know I have all the wires hooked up correctly. The vehicle stalls and rough idle when warm regardless of being remote started or not. It is just back in my shop because it started happening after the install

I went by Directechs, I believe there was a problem with GM cars if the ACC wires weren't properly connected, check whatever guide you used, if it lists one IGN and 2 ACC, set it up the same.

Just looked again, 2 X IGN and 2 X ACC, your problem is the second ACC wire. These vehicles are unknown in Europe but I remember from this site there were problems with GM vehicles around 05 ref the second ACC not being connected causing all sorts of problems inc. the engine warning light coming on.

You should have the following:- Red constant 12V+ supply. RED / white constant 12V+ supply Yellow start IGN 1 pink IGN 2 white ACC1 orange ACC2 brown Bet you haven't connected the brown.That wire colour rings bells to me.