3200GT idle and jerky in the first few minutes

Contigo

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Drawing a blank with this one mate. Need to get back to the garage and ask them to investigate. Something must have been disturbed during the work...
 

onlinesys

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Drawing a blank with this one mate. Need to get back to the garage and ask them to investigate. Something must have been disturbed during the work...

Definitely a loose connection or something. Third time back to garage including the coming one within a month! Very nice!
 

Contigo

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Frustrating I know. I've decided my car hates my home town as soon as I get within a mile of home the CEL comes on. Lost all pedal control and had to reset I think the PedalPot is finally giving up after my rewiring trick. I will go the contactless route which will completely overhaul the whole DBW system. The interesting thing about this time was that to get the PedalPot working again I disconnected the white connector at the top where the PP connects to the block. Left it a minute and it worked. I do wonder if it is the cabling rather than the actual pot but I guess I'll never know until I replace the pot and see. Got to love these cars.....
 

onlinesys

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Yes, the 3200 is a typical Italian beautiful hot gal with high maintenance
and bad temper every now and then yet you will miss her if she is not around.
Will let you gents know the cause of problem hopefully some time next week.
Many thanks again for all your input and help
 

onlinesys

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A bit of update this morning although car will only be returning to the Indie on the coming Saturday.
Connected OBDII cable to car and realized CEL is on and I could use the 'Clear DTC codes" option to clear it
although the information is blank on the screen of the Unidiag2000 software. Tried to load the data file of the
software and I could now see the info of the DTC codes.
What exactly is the error message?
 

onlinesys

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Just did a search again the 0x0331 is Knock Sensor. I just had the water pump changed and had this problem afterwards.
Do you think it is something to do with the loose connection or if it is really the Knock sensor is dying?
Thanks again
 

Contigo

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There are two knock sensors, one front and one back.

The knock sensors invariably fail because the vehicle is leaking coolant into the vee, which in turn gets into the sensors. Normally the tell tale sign is the coolant level being low. Was it low?
 

onlinesys

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Morning Phil,
There was a leakage in the water pump few weeks back so the coolant level was low (very low) but no CEL until
a couple of days b4 bringing the car to Indie for water pump replacement (wait for a week b4 the water pump arrived)
After replacing the Water pump, car was back home and there was a slight jerky on throttle in 2 days and gradually
reluctant to start and not idle when cold.
Would it be the coolant leaked to the knock sensors and caused damage?
 

onlinesys

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I guess I should change both knock sensors and order the crank sensor for precaution as it is not expensive
 

Contigo

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Yes common problem once coolant leaks it leaks down in the engine V and that soaks the sensors. Again a typical design flaw from our Italian Friends.

Yes both sensors should be changed when doing the job. One other thing worth considering doing at the same time are the 4 short water pipes as these OEM parts are simply poor quality and will perish in the end. Well worth fitting a much more durable silicon pipe in place.

part no 585089700 for the Knock sensors.

The 4 pipes I refer to are in the picture (fitted with more durable blue silicon hose)

IMG_1279.JPG
 

onlinesys

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Many thanks Phil,

Any info on the silicon pipes? Where did you get these? Hope these are not complicated work
 

Contigo

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I have not had it done on mine (or at least not sure as I've not had the inlet manifold off), it is work that I will do should once I get around to it but many on here have replaced parts like those pipes and the heater pipes whilst in the process of changing the knock sensors.

The pipes themselves are I believe 32mm diameter and you could just but a decent silicone hose and cut them to fit.

Some people sell the whole lot on Ebay....

http://www.ebay.co.uk/itm/Maserati-3200GT-Silicone-Coolant-Hose-kit-Roose-Motorsport-/221017255490

If I was in a hot country like HK I would probably prioritise this job :D
 

onlinesys

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Very nice Phil. Will try to order a set as it could be very hot in a couple of month like 36 degree C
A bit of more update this morning as the car starts and idle normal. Not sure if it is not really in cold
Condition as I drove it last night and only 8 hours since I switched it off.
 

davy83

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Yes common problem once coolant leaks it leaks down in the engine V and that soaks the sensors. Again a typical design flaw from our Italian Friends.

Yes both sensors should be changed when doing the job. One other thing worth considering doing at the same time are the 4 short water pipes as these OEM parts are simply poor quality and will perish in the end. Well worth fitting a much more durable silicon pipe in place.

part no 585089700 for the Knock sensors.

The 4 pipes I refer to are in the picture (fitted with more durable blue silicon hose)

IMG_1279.JPG
what a clean engine!! and you painted the water manifold and the rocker covers too! wow nice job sir
 

Contigo

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Not mine Davy but I aspire to this. I also aim to stove enamel the plenum too but I have a list as long as my arm for this car :D
 

onlinesys

Junior Member
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133
I bit of update on the jerky idle and OBDII connection issue that might be useful for other owners.
I had ordered the 2 x knock sensor and also the crank sensor with some water pipes/sleeves from Eric of Maseratispares.
Indie had cleaned all connectors and now the car could start normally every time and you could hardly notice the unsteady
idle although there will be CEL on if I switched off the car for more than 24 hours. Funny enough that the CEL will disappear
if I restart the car after it is fully warm-up or I use the car again within 24 hours. Also the car drive a lot smoother after
the connectors clean-up too.