Too juicy??

[nutco]

undo the connector to the coolant temp sensor, (the one on the right hand side of the engine at the back under the inlet) by doing this you are telling the ECU that the engine is up to temp, now start it and take it for a run, this was the only way I could start mine when my CTS went totally pears, it just kept flooding the engine,

[Laird Scooby]

Originally Posted by aardvarkash10

@80mph regardless of where, you should EXPECT significant fuel use.

You are pushing a 1.7 tonne housebrick through 2.1m2 of air resistance and dragging a similar-sized vacuum behind you. That all comes at a cost.

Agreed but not 10mpg!

Could also be worth crawling underneath with the engine running and checking for fuel leaks. A favourite for developing a pinhole leak is the short link pipe between the main pump and filter, also where the 12mm bore fuel hose from the tank meets the rigid pipe feeding the main pump. On 95 on cars where there is only one pump this will obviously be different.

[Laird Scooby]

Originally Posted by nutco

undo the connector to the coolant temp sensor, (the one on the right hand side of the engine at the back under the inlet) by doing this you are telling the ECU that the engine is up to temp, now start it and take it for a run, this was the only way I could start mine when my CTS went totally pears, it just kept flooding the engine,

Not quite correct - you're telling the ECU the CTS is MISSING!

It goes into Limp Mode and defaults to a preset value which under the circumstances is (and was on yours) better than the value the CTS was delivering to the ECU.

However it may prove useful as a diagnostic work-around if the OP can't use the multimeter to test the CTS but isn't a guaranteed test.

[nutco]

Originally Posted by Laird Scooby

Not quite correct - you're telling the ECU the CTS is MISSING!

It goes into Limp Mode and defaults to a preset value which under the circumstances is (and was on yours) better than the value the CTS was delivering to the ECU.

However it may prove useful as a diagnostic work-around if the OP can't use the multimeter to test the CTS but isn't a guaranteed test.

NOT CORRECT, We did an exhaust emissions test on mine with the cts unplugged we then put the new cts on and did another reading after taking the car for a good drive and both readings were the same,

[mhuk]

My 19T w/ mapped ecu get's 20mpg with mild boosting.

[Laird Scooby]

Originally Posted by nutco

NOT CORRECT, We did an exhaust emissions test on mine with the cts unplugged we then put the new cts on and did another reading after taking the car for a good drive and both readings were the same,

If it wasn't correct, Volvo wouldn't waste their time and money fitting a CTS now, would they?

For some reason, only half my post came through, internet problems!

Anyway, FYI, the usual default coolant value assumed by the ECU in Limp Mode is 60C so cold starting would be effected (lack of enrichment) with the CTS unplugged and hot running wouldn't be effected, even on an emissions test as it would be within the scope of the Lambda sensor and ECU to alter the fuel trims enough to get a satisfactory idle and emissions.

Therefore your "proof" is nothing more than coincidental, indicating the fuel trims were pretty close to optimum before your CTS went for a can of worms.

[nutco]

Originally Posted by Laird Scooby

If it wasn't correct, Volvo wouldn't waste their time and money fitting a CTS now, would they?

" Volvo wouldn't waste their time and money fitting a CTS now," Because if they had not fitted one cold starting would be a night mare, thats why,


Therefore your "proof" is nothing more than coincidental, indicating the fuel trims were pretty close to optimum before your CTS went for a can of worms.

Nothing coincidental about it the slightest difference in temp readings and fuel trims would show on the exhaust readings, this was explained to me by a rolling road tuner mate of mine

[mocambique-amazone]

Originally Posted by nutco

NOT CORRECT, We did an exhaust emissions test on mine with the cts unplugged we then put the new cts on and did another reading after taking the car for a good drive and both readings were the same,

Controlled at idle speed?

Will tell you nothing about a working CTS.
At that moment when the Lambda-sensor is hot enough to spend voltage this part of the system will regulate the enrichment at idle.

Good luck, Kay

Now I did read post 27
On a rolling road it should be different while acceleration

[Laird Scooby]

Originally Posted by nutco

Nothing coincidental about it the slightest difference in temp readings and fuel trims would show on the exhaust readings, this was explained to me by a rolling road tuner mate of mine

What Kay said ^^^^^^^ saved me some typing!

As for the CTS, the K-Jetronic doesn't have one but manages to cold start without a problem.

[deeman940]

O.k so yesterday i fitted the new CTS and whilst i was there i thought i would have a go at fitting the silicone Do88 hoses i have had lying around for a while along with the new FORGE MBC..
Upon fitting i found one of the hoses that goes to the idle control valve was split badly....Excellent i thought, that HAS to be the cause of the problems. ...
So i went for a spin and whilst it is running and idling better, i still have many of the same problems... The idle is still fast after a bit of spirited driving although 300 rpm lower, i am still getting the odd backfire, which would indicate rich running.and still stalls occasionally too
It is holding boost and spooling quicker now but i reckon that is down to the new MBC...so overall not a bad result but still not quite cured. Could it be the FPR or the idle control valve? i have to uprate the FPR shortly anyway...