New 3200GT owner

[hugy]

Hi.
I have a problem with I thi k Maybe an air leak.
My car is 1999 3200 GT.
The engine revs up to 1400 rpm every time I take my foot off the accelerator and sticks there for about 10 secs before gradually going down to 1100 rpm.
I have no warning lights and the car does not go into limp mode.
Also on cold start it hunts up and down for 5mins before settling at 1000rpm.during this time I cannot drive the car as its tricky with the uneven tickover.
The TB is not sticking at all.

 

[davy83]

Thanks for the compliments. It’s a great looking car but it’s not quite sorted yet and I need some advice please.

Firstly, the engine management light is still showing. A lot of historic codes due to the car not being run much in the past few years, dead battery etc were cleared and have not reappeared. Used a friend’s Launch crp129 scanner. The only errors now showing are re the knock sensors on bank1 and bank 2. I plan to replace the knock sensors plus whichever hoses etc. you guys recommend at the same time. Any advice welcome.

Secondly, the idle speed appears to be too high. In Park it hunts between approx. 1000 and 1200 rpm, in Drive it is steadier at around 1000 rpm but this still seems too fast to me. Can the idle speed be adjusted? I have seen nothing to suggest that it can. And can anything stop the hunting? The throttle body has already had the position sensor upgrade, so short of cleaning it I don’t know what else to try - unless changing some air hose or gasket might cure an air leak. Again any advice welcome.

I am guessing that there may be other error codes which the Launch reader can’t pick up. My local garage had similar issues with their machine and I haven’t taken it to a specialist because, up to press, I haven’t been confident enough to drive the car any distance. Can anyone recommend an obd2 scanner, of reasonable cost, which can read Maserati codes? Multiecuscan software has been mentioned elsewhere on the forum.

Factory setting for idle speed is 950 rpm so the rough idle speed is correct, and no its not really changeable and you don't want it much lower than that as the oil pressure starts to drop off quite quickly below that when its hot.
The hunting idle can be a number of things but most likely caused by the contactless sensor fitting on the throttle body not being set up right, and it can be cured but it can also be a little complicated. PM me I can try to help you out there.
Knock sensor errors are pretty common on cars that have been sitting for a while. it might be worth driving it a bit and see if the errors clear up, I think sometimes its just condensation, and a longish run with the knock sensors getting proper warm dries them out?