Talk Morgan Forums Morgan Sports Cars Morgan Aero 8, 2012< Plus 8, SuperSports, Coupe & Aeromax Aero 8 series 4 RPM Blip when cold

Hello team…I have a 2009 Aero 8 owned from new. Recently, when starting from cold the engine will start, idle normally and then momentarily increase RPM as if the throttle has been “blipped” it will occasionally do this one more time whilst cold, usually just approaching an intersection, which is quite unnerving! Anyone experienced this?

Repeat post following your first Ian.

Suggest downloading this info on N62 engine. It describes how the valve lift and timing via VANOS control the power demands however there is a conventional throttle valve used during cold start. I quote:

Airflow is controlled by the throttle valve during the starting procedure when the air temperature is between 20 ºC and 60 ºC, . If the engine is at operating temperature, it will be switched to non-throttle mode approximately 60 seconds after start up. In cold conditions however, the engine is started with the throttle valve fully opened because this has a positive effect on the starting characteristics.

I would suggest switch over of one control to the other may be the issue. Start by checking temperature sensor maybe. Then throttle valve sticking.

Sound's like you might have a dirty idle control valve, a quick clean with brake cleaner and a wd40 lube and i think you might be sorted.......Em

Hi Ian, I had a 2016 Aero 8 and now have a Aero Plus 8 and both have the tendency you describe but only when cold. The plus 8 tends to have what I liken to a cough after initial start with around 800 RPM then after the cough the revs drop to 500 / 600. The Aero took longer and usually the car was underway and did as you described which was disconcerting initially but had the car for 4 years with no ill affect. As they say "They all do that sir". Hope this helps. Ron.

Does an N62 engine have an IACV Em? Usually engines with FBW throttle pedals don't.

Richard. I thought the 2009 Aero has the m62 engine the 4.8 not the 4.4 n62 and was sure it had an icv might be wrong though. If it hasen't do the simple stuff first trace it back to the dreaded Maf sensor a well known aero issue and simple fix. Em

By the time the M62 was first used in the Aero series they had already switched to FBW throttle control. I think this happened around 1998 when VANOS first appeared on this engine albeit on inlet only. As such it didn't need an IACV. Whilst Morgan used the M62 in both 4.4 and 4.6 (GTN) variants they switched to the new design N62B44 in 2004 for the Aero Mk2 with double VANOS and I believe in 2007 to the 4.8 variant N62B48. They all had FBW throttle though.

Sounds like it could be a MAF sensor?