Merc63

I switched to a smaller pulley, the car was running fine initially but now it won't cruise. I keep getting huge power loss on and off, it dies than comes back on so hard it hammers the driveline.

Pulled a p0191 code.

105,000km on car, anyone else get this? Under load or full power, the car is a rocket and just made great power at the dyno.. but it won't cruise and even died a few times on me after I started it. I went to the track and it pulled great too.

Celicasaur

I wonder if STAR gives operating ranges for the fuel pumps under varying amounts of load and lets you know if they're both in good order

A simpler fix would be a nice fuel rail sensor I suppose.

Merc63

Pretty sure my fuel pumps are toast, car will barely start and idle.

Got a load of codes last night, rich bank 1/2, fuel press codes etc.

BLKROKT

Fuel pumps are like $300ea. Might be good maintenance at your mileage and considering how hard they've been working.

Merc63

Where $300 each? I was quoted $1500 CND, for two at the dealer.

BLKROKT

I just looked them up on OEDiscountParts and that's what they were

BLKROKT

Mort

Unfortunately OE Discount Parts does not ship outside the continental US which is a complication as Merc63 is in Alberta. Maybe transship or use a border pick up place if there is one.

BLKROKT

I'd ship it to you if you want to pay for shipping twice

Merc63

I have the pumps from my wrote off car, I'm going to try those first. Thanks guys

Merc63

Well I had some extra pumps and control modules from my smashed car, I switched them over tonight and still the code came back... I went to a buddies and switched fuel pressure sensors, code gone so far, knock on wood.

So it was the fuel press sensor giving me all the grief... I wonder if it just **** the bed or this 116octane Fuse race fuel (unleaded) took it out?

Back to racing this weekend and installing the meth kit now.

Celicasaur

Good news - glad to hear it's sorted now and thanks for posting the solution

Alex.currie44

Fuel pressure in the fuel rail it seems.

https://www.autocodes.com/p0191_mercedes-benz.html

deadlyvt

Where are you getting meth in Alberta ? I can't find it anywhere

Merc63

Wheels plus, boost juice.

Mort

I used to use Methyl Hydrate from the hardware store. It is 99.9% pure methanol. Locally it is $11.00 a US Gallon/3.78L.

Viktori

Hi there, sensor was in engine or on gas tank?

Merc63

Sensor is on end of fuel rail.