4200 - Vapour canister purge valve

TimR

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2,656
A simple code reader should be able to tell you what engine temp the ECU is being told it’s running at as the obd2 port gets its data from the ECU.
Sure - 87.8*C
Counter value against the error code (PO128) = 1 ( temp recorded at the time appears to be 59 )

Does the counter value denote the number of instances...?
 

doodlebug

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913
A simple code reader should be able to tell you what engine temp the ECU is being told it’s running at as the obd2 port gets its data from the ECU.
I agree, but the initial fault was intermittent and never manifested itself when in for repair. Lancaster's, McGrath's and Grimaldi all have SD2/3 diagnostic kit. I can't believe they were all complicit in denying any fault was present.
 

Oneball

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11,075
Inline with what doodlebug said it would be good if you could read the ECU temp when it’s playing up.

The P0128 code is saying is that the ECU expected the car to be fully warm but it wasn’t.

Clear it and see if it comes back. But could be thermostat or fan related.

Does it take a long time to warm up?
 

TimR

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2,656
Just to add to this..
I have just experienced the poor engine throttle response issue in unmistakable guise this morning...
The car was cold. It disappeared after the car was warm but it also generated a fault code. PO421 ....
The code could be triggered by faulty O2 sensors but having looked at the O2 sensor data, and frankly dismissing these as out of spec, I tend to think not...
The hotstart thing as was explained, isnt going to happen because of open loop ..So even more to suggest Im looking at the wrong thing ( Ive now changed the coolant temp sensor, crank sensor and purge valve..)
I want to ask how common is it that the facelift catalytic converters fail...?
I know the early cars had issues. I fear I need to look at theses closely..?

PO421-cartalytic warmup efficiency below threshold ( bank 2 in my case - )

Poor starting may come from here. ( Or am I reading too much google for my own good ?) Poor running/throttle response would also be a symptom ( deffo when cold I understand?)

Thoughts...?

cheers
 

Oneball

Member
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11,075
With that code I’d check the secondary air pump system. There’s a peirburg pump, some electrics, pipe work and the silver can like valves.

Pumps can seize and valves stick.

Doesn’t usually affect starting but will impact initial running when cold.
 

TimR

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2,656
With that code I’d check the secondary air pump system. There’s a peirburg pump, some electrics, pipe work and the silver can like valves.

Pumps can seize and valves stick.

Doesn’t usually affect starting but will impact initial running when cold.
Good point
Not clear how a secondary air pump issue doesn’t pop a related code( it has in tha past)
What you say makes sense....
 

hashluck

Member
Messages
1,515
With that code I’d check the secondary air pump system. There’s a peirburg pump, some electrics, pipe work and the silver can like valves.

Pumps can seize and valves stick.

Doesn’t usually affect starting but will impact initial running when cold.
This was my thoughts. Check the pipe that runs from the pump as well for leaks
 

Oneball

Member
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11,075
Good point
Not clear how a secondary air pump issue doesn’t pop a related code( it has in tha past)
What you say makes sense....

Only speaking from BMW experience here but a stuck valve rather the pump doesn’t often throw a code.
 

TimR

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2,656
Cleared the code and its not returned..
They do love to pop a EML these cars, blimey !

On another note, Ive not had the start issue for a while...dare I venture to suggest its cured?
Also, replaced the spring, non-return oil valve in the top & it's stopped rattling on start up too....
Happy daze!
 

jluis

Member
Messages
1,703
My 3200 has the hot start issue (on hot days mostly) and a leaking purge valve (Tested it with a vacuum pump) meaning that it will suck a rich mixture when starting.
It also smells of fuel like described here.
I found that on those hot days if I open the gas cap to let the pressure out, it will start easily afterwards.

I have the valve to replace it but haven't found the time yet.
 

paul328

Member
Messages
129
Hi
When I was driving my car today the EM light came on and a fault code was displayed of PO128 Coolant Thermostat coolant Temp below Thermostat Regulation temp. I had noticed the car seemed to be running quite cool with the gauge only getting to about 1/4 despite a 15 mile run in one direction.

We reset it after reading the code but the temp is the same.

On the way home i noticed the car suddenly appeared to loose a bit of power but def not limp mode and appeared to clear. An E symbol came up on the Green display which normally shows outside temp. Once restarted the outside temp came up

Probably unconnected:

A few times the car was difficult to start when hot. Today I stopped for fuel and the car missed the part to start and needed to be turned over about 6-8 times before catching. The EML was on. I have only really put the car back on the road yesterday and been SORN'd or off road/hardly used for 3 months. This is the 4th time in say 8 months it was difficult to restart when hot.

I have always found the car idles high. The only other I drove did the same. The fans appear to be on when I start the car although I usually have the air con on.

These could be separate faults.

For the Fuel Washer Valve 180861, how often are these to be changed?
For the Fuel Diagnostic Pump filter 183221, how often are these to be changed?
For the Fuel Vapour filter 22074, how often are these to be changed?

I see from previous threads that many have had similar issues.

Seems like:

1. Hot starting could be Fuel vapour/washer filters.

2. Cool running PO128 could be Thermostat or Gauge sender. Although not sure that makes sense as the gauge reads temp not sends it???

Any help appreciated.

Paul
 

Mr S

Member
Messages
821
I had hot start issues a couple of years back, and swapped the coolant temp sensor, washer valve, vapour canister as well as change the rocker gaskets. I say do the easy DIY stuff first, washer valve and purge canister, see if that helps, then coolant temp sensor (DIY but just a bit fiddly), then rocker gaskets. I didn't identify specifically what was causing the issue, as changed them all during the first lockdown.
 

TimR

Member
Messages
2,656
Rocker gaskets...How does this impact hot start issues exactly..?
Canisters need changing @4 yrs according to Maserati. I'd assume regular usage at that ( circa 15K a year or whatever) They are a bit of a pain the **** but a regular service item ..Remove boot lining to get at it.
The purge/cleaning valve- cheap and easy, as others have said. ( if avalable- ) Not sure of the service interval on either this or the fuel filters.

I just had the PO128 code a few weeks ago. I noticed the car was running lower temps too..Put it down to winter ambient temps' at first.
Strangely, the car was warm after 25 mins running but parked up for 30mins, it popped this code on the return home. Im going to swap out a thermostat for peace of mind, despite it hasnt re-occurred. I stopped using it over the winter as soon as I didnt absolutely have to so it may still be lurking...
I guess its an age thing. I could have changed it out when I had the front clip and rads off last year but figured, if it aint broke etc.
That's what you get huh !!