Volvo 164 73' horrendous fuel economy!

Hi Jörg,

as Australia was pretty early to apply exhaust gas controls I assumed that Al would have a US engine type. But you are correct if it is an European engine type, then 015 would fit.

So Al, which one do you have?

Hi Al,
you can do a last check:

I had a MAP sensor showing a vacuum-loss-behavior similar to yours.

I opened it, inspected it and couldn't find anything suspicious.

I noticed the vacuum got lost at the plastic bloc of the electric contacts.

I applied some glue around the bloc and the vacuum loss was gone.

Regards
Norbert

Hi Norbert and Al,

not to raise too high expectations: I have never seen such a vacuum leak on a MAP sensor. So Norbert your case seems to have been a very exceptional failure. I do not recommend to disassemble the MAP sensor. I have too many with bent or lost parts.

HI Volker

yes mine is the E engine which is the high compression version. thankfully no emissions crap on my engine so the 015 sensor is the correct one for my engine.

and of course i will not throw away such a valuable piece of the injection system. im not mad haha.

if i can not locate an affordable replacement i will attempt to open it however i doubt my skills would be sufficient to replace the leaking diaphragm or attempt a repair on it.

i will hold my fingers crossed that i can locate a non leaking unit

cheers

UPDATE: i have found a seemingly good working type 2 with the correct serial number. now this did improve my air fuel ratio/ lambada however not quite where id like them to be i havent driven far enough to see if its made a difference to the economy.

However i found another good type 1 MAP sensor and weirdly enough the engine seems to be getting better results on the o2 reading which i find quite strange given its not the correct type. however i will add it has screws so it may have been repaired in the past.

Hi Al,

you cannot really compare with MAP sensors of different type and no. Is the spare one you found with rivets and if so what no. is printed on the top right rivet? And of course potting should also still be okay. I remember we once discussed a case her also from Australia where someone had drilled into the potting, destroyed the screws underneath and later repotted it.

There is nothing unthinkable in the world.