Cooling issues

[Vigri]

Air to Fuel Ratio is perfect when driving. When accelerating hard, it tends to get a little rich sometimes (~13,x) but when idling with warm/hot engine, it get lean (~16-17).

[Thorsten Ruge]

Sounds like your air temp sensor in the inlet plenum is faulty? Did you ever clean out the pins inside its connection plug? Is the sensor tip contaminated by oily residues? If taken off already, check the linear run from/down/up to 0 connected to an Ohm Meter by running a hair dryer,- watch out, the little plastic cage around the tip melts fast!

"but when idling with warm/hot engine, it get lean (~16-17)" sure, because its running to hot and regulating against it as long as you do not find the reason.

[Vigri]

I checked the air temp sensor and it the tip seems to be contaminated by oil as you said. I ordered a new one and I should arrive on Monday so I hope new shows how much it helps.

[Vigri]

I replaced the air temp sensor and car now works better, but it didn't help with overheating problem.

[fab]

Air to Fuel Ratio is perfect when driving. When accelerating hard, it tends to get a little rich sometimes (~13,x) but when idling with warm/hot engine, it get lean (~16-17).

This is the point Vigri. The manual says the CO has to be 2.0-2.5 % when idling which should be 13.6 A/F.
Anyway you do not loose much power by setting the A/F too rich, you just cool down the engine and prevent knocking.
Philippe

[veith2224v]

you may want to check catalyst (could be clogged) and lambda sond if engine still runs (far) to lean before fiddling with the CO-screw! Do You loose liquid coolant?

veith

[Vigri]

Catalyst I replaced just last winter, so this can't be the problem. I'm getting a new better fan next week, lets see how it helps the cooling problem on track.

[Thorsten Ruge]

Do you loose coolant like Veith did ask above Vigri? If not at all, try a bigger radiator, the "tropical" versions like from ebay in US, AUS etc., mine is the copper made Californian version from River-Valley/HMI,- bigger is better anyway!

If you can not get possibly an affordable one made/adopted from your local radiator companies, that's the right one, Lenny is a nice guy and you can always negotiate prices with him.

http://cgi.ebay.com/ebaymotors/Maserati-...ccessories 

[Vigri]

I haven't noticed any coolant loss as far as I can tell. I already got a custom radiator made and they said that they made it as big as they could fit in there, but it didn't help.

[Vigri]

Can anyone tell me what the temperature drop between ingoing and outgoing radiator ends should be? I measured mine whit a IR thermometer and it was only about 4C and to me it seems quite small.