P38A Struggles for power under load V8 4.0 Gems (1997)

Hi,

Driving along in my 1997 P38a 4.0 V8 the other day and went to overtake somebody and struggled to get power, got to around 2500rpm and I could feel the engine struggling, feels like the brakes are stuck on when trying to accelerate.

Doesn't do it all the time, but it did happen again on the way to work this morning. If I just cruise at light throttle no problem when I go to accelerate at WOT it struggles but as said previously it doesn't do it all the time.

Haven't noticed a problem when stationery, i.e. in Park the engine revs freely all the way up to the limiter

Not an expert (hence the post to get peoples ideas) it feels to me like a fuelling issue like a weak pump. Vehicle had a service a few months ago and had a genuine fuel filter fitted so cant see it being that but then again nothing would surprise me.

No fault codes stored, no warning messages or lights showing in the cluster.

Has anybody had anything similar in the past?

Thanks

Look in search bar - ‘Limp mode’ is my guess.

Running LPG? Plugs / leads?

MAF sensor?

Unplug the MAF and take her for a spin.

1) No LPG on my car.
2) 8 new plugs were fitted in June during the service, I did take them out last night but they looked ok, leads how do I test them?
3) Havnt done anything with the MAF sensor but if that was duff would it not log a DTC? I do remember in the past disconnecting the MAF sensor and the engine just dies so not sure what unplugging the MAF will achieve? Should a GEMS engine run with the MAF sensor disconnected?

Thanks

With Maf unplugged ECU will use a set of default settings to run car. Not the most economical way to run but the car will run far better than if Maf is faulty. Just unplug take for a spin if it improves more than likely faulty Maf if still same problem lies elsewhere and would recommend diagnostics