9-5 Aero hesitancy at speed

[MoonMonkey]

Hi guys, Looking for some advice. Like a prat I ran out of fuel in the Aero a couple of weeks ago. Since then I have been experiencing a slight hesitancy at motorway speeds on part throttle - say 70 mph (2,500 rpm). It doesn't do it all the time just now and again. I can't help but think it's linked to running out of fuel a couple of weeks ago... I have probably used a full tank since. I did think it could be the fuel filter but surely if that was partially blocked wouldn't I get the symptoms all the time...??

Anyone got any thoughts..??

[boolay]

You could try resetting the ecu by taking the fuse out for 5 mins.
Other than that, it could be the CPS, DI Rail or MAF. HAve you're spark plugs been replaced within the last 2 years?

No engine check light I assume?

[MoonMonkey]

Not sure about the plugs to be honest. Only had the car about 5 mths. I did try and take a plug out but don't have a small enough socket.

So far I've checked all hoses to / from the MAF and throttle body - all seem ok. Also disconnected the battery and have re-fueled with super unleaded. However, I took it for a blat and have to admit I think it's getting worse..!!

I will try removing the fuse as suggested and think I will also look at changing the fuel filter. However, under load the car revs / turbo spools up nicely it's just under part throttle that it happens which is stumping me a bit.

ETA: no check engine light showing

Edited by MoonMonkey on Wednesday 15th September 20:57

[carlosvalderrama]

My '02 9-5 Aero had a similar issue when I bought it, and it also used to hunt under constant throttle. Quite noticable when cruise was active, I initially thought it was just rubbish cruise control. Eventually traced it to the APC or boost control valve. I replaced it and it's now OK. Used valves can be had off ebay for a few quid, might be worth a punt to eliminate it at least.

[steaknkidneypie]

fuel filter may be an idea to check, incase there is any muck in it.

HTH