92 W124 sudden power loss - Remedy ?

[Chris_]

Hi,

a 92 2.5T - runs fine however sudden loss of power - still very driveable at all speeds but lower fuel economy and less available power for acceleration.
1) I did the turbo actuator mod
- using a boost gauge checked that boost is building
2) Removed and checked the function of the ALDA - ok
- I cannot remember if I checked for presence of + pressure at the ALDA port ( I will check that)
3) Fuel supply is good through lift pump to injection pump

a) Aside from the ALDA and its function has anyone had an issue where the IP itself caused a power loss ( internal linkage etc ) ?

Thankyou

[shertex]

Have you replaced the fuel filters?

[Chris_]

Yes fuel filters have been replaced.

Thankyou

[mespe]

I would guess you have a leak in the fuel line, and every now and then air gets into the fuel line.
Or possible something in the fuel tank.
Not familar with the 2.5, but if you stick a "T" in the fuel line, before the lift pump and hook up a vacuum gauge, during the loss of power, if the vacuum increases, you have a clogged screen, or other restriction before the "T" if vacuum doesn't rise, you probably have a leak in the fuel line.

[benmack1]

Just went through something like this myself. From your post the way it is worded, you mention you checked the ALDA and it was OK. What does that mean? Did you remove the alda physically from the IP and try to drive like that. If not, you might want to give that a whirl. Sounds like you are providing air but no fuel. That would answer the other half or the equation and give you full fuel to go with your boost. If you already did that, then apologies for misunderstanding your troubleshooting comments. good luck.

[sixto]

Is the shutoff actuator releasing completely when you turn the key to glow?

Sixto
87 300D