Hdi90 power loss

[charlie328]

Hello, looking for some experience on this engine.
Car has recently lost power on uphill sections of motorway culminating today in an Engine Diagnostic warning light and frequent noticeable power loss to around 2000rpm which resets after a minute or so.
Are there any usual suspect components to cause these symptoms?
Thanks in advance, Charlie

[Doggy]

Hi Charlie and welcome aboard.

Fuel and air filters OK?
What age is your car and do you know if it's got a Bosch or Siemens fuel system?
(The former has an in-tank lift pump and the latter a priming bulb under the bonnet).

[GingerMagic]

Also, as a cheap diagnosis, try unplugging the MAF, its the black tube on the right between the air box and the corrugated bit - there will be a grey plug on it ( I think )

[GingerMagic]

Oooops, maybe 90's don't have a MAF....

[charlie328]

Hello, I can't fing a priming bulb and can hear a lift pump with ignition so presume I have a bosch. The car is a 1999.
I disconnected the MAF and she wouldn't rev above 2000rpm?
Fuel filter is good. Air filter was dirty and the forward part wet. Going to fit a new one tonight but I blew it through anyway with compressed air. Could it be that simple?
Charlie

[markw]

Someone on the Coupe forum unwisely drove through some deep water recently after all the foul weather we've been having.
He was suffering from almost exactly the same symptoms as you describe. He dried out the fair filter and it's been fine since.

[jonsowman]

Just to clarify, 90s do have a MAF but it's only to monitor EGR function -- it isn't used for fuelling calculations. Unplugging it will still cause limp mode though, hence the not revving >2000rpm

[Doggy]

Hello, I can't fing a priming bulb and can hear a lift pump with ignition so presume I have a bosch. The car is a 1999.

It will be Bosch then. Lift pumps sometimes fail, but usually go intermittent for a while before dying.

Try the air filter first and let us know how you get on.

[charlie328]

Hello again,
So, just replaced the air filter. Found water around the MAF and upstream which has been dried out now.
On closer inspection of the MAF it looks like we may have found the fault? There is what look like two little fuse wires which are probably sensors. One of them has broken and is missing. Can anyone confirm there should ordinarily be two or am I barking up the wrong tree on that one? going for a test drive anyway.
Really appreciate the help though, thanks.
Charlie

[madmadmax]

there should be two one for air speed and the other for air temp, so fined a siemens branded for as cheap as you can.

[Busman]

Does the HDI 90 have a throttle position sensor? This sounds remarkably like the symptoms mine had when that failed.

[jonsowman]

Where are you based? You could do with having fault codes read

[charlie328]

Hi all,
Cleaned the water out of the inlet manifold, replaced the air filter and damaged MAF. She now pulls like a train with no warning light. Really happy. Thanks all for your kind help, much appreciated.

[jonsowman]

Well done, glad it's fixed

[Doggy]

Good stuff.