AFM's on 255lph pump at idle

[hopalong_neil]

Ive just fitted a TD uprated fuel pump and noticed at idle its running significantly richer. Before change on warm engine wideband was showing around 14.2 but now its 12.5.

Anyone had anything similar?

[5T4R7ET N/A]

Has the car been mapped before fitting new pump?

[hopalong_neil]

No, was running a JAM ecu which was fuelling fine with a td04 @ 0.9 bar

[5e colin]

feul pump makes feck al diference 125l 255l or 355l afr stays the same !!! its controled by the feul pressure regulator

make sure engine is up to temps

if you have the pfc fitted yet ??? then its a setup isseu turn down the nob inside !!

[hopalong_neil]

No Colin, pfc not fitted yet, still running on JAM ecu.

Only thing i have changed if the fuel pump.

[Stu]

Are you checking the afr when its up to temp? Unless you've changed the base fuel pressure it should be exactly the same.

[hopalong_neil]

Yeah engine is fully warm, cold starts at 10 then only climbs to 12.5 max

[Stu]

Thats interesting. Do you have a stock fpr on it?

[H_D]

Hows it fuelling on boost?

Hows it fuelling on boost?

[TrisK]

If the pump was seriously knackered before and wasn't making enough pressure then pump will affect you afrs

Probably worth doing the whole unplug and relearn procedure on the ecu

[5e colin]

did you calibrate your wideband sensor ?

[hopalong_neil]

Yes, stock fpr

Not driven it yet

Have AEM wideband, no need to calibrate as far as i am aware.

Bit of a long shot but would the tank vent make any difference? Have noticed the last few times I've filled up a lot of air either escapes or enters.

Ran it for about an hour yesterday stationary after changing pump and this morning same thing...

[5e colin]

wel if you think its the vent then start her with petrol cap off and see if it change

i dont think it make a diference neil

[hopalong_neil]

Ok, no difference there.

Def running rich, checked plugs and they were all sooted up.

Might try changing o2 to see of that helps but would be a coincidence if it died at same time i changed the pump.

What controls cold start on the gt, is it a sensor?

[5e colin]

ecu temp sensor and 02 sensor are the main 1s on stationary / cold start

could settle down to tho after some blasting seen that before with engines that havent driven for long periods

[Duduglanza]

whats the afrs on boost? have they gone up too? what pressue is the reg setup?

[hopalong_neil]

Not been able to get the car out to drive, cold start afr drops off the scale and car barely runs.

Stock fpr fitted

[gorganl2000]

i suspect an ecu reset and some driving will get you back to normal afrs

[H_D]

Car will run rich after an ecu reset and usually trims itself after 50-100 miles on pnp ecus

[Ollieh17]

I had the same issue after fitting a 255lph

[hopalong_neil]

I had the same issue after fitting a 255lph

Did it improve?

[hopalong_neil]

Car will run rich after an ecu reset and usually trims itself after 50-100 miles on pnp ecus

Ok, if i can get it running and warmed up enough to drive I'll give it a go

[Ollieh17]

Nope

[hopalong_neil]

Ok, quick update after a few hours work today. Have fitted a sard fpr and adjusted it to 2.3 bar and its still overfuelling loads so it seems that its definitely something demanding more fuel be it a sensor or ecu.

So next thing i think is change out o2 sensor as this would seem the most likely culprit.

Also to check sensor wiring am i right in thinking that i can test continuity between ecu pin and sensor wire plug? Anyone know what pin it is?

[adzy]

Have the same issue with my 255 pump fitted, started running very rich after, also changed the O2 sensor with didn't change anything.

This was also before I fitted the p+p ecu