T5M bogs when getting off the gas

Post by **Clemens** » 12 Oct 2018, 11:11

alright. if it takes that long i might just pour a bottle of injector cleaner into the fuel tank and drive. and maybe replace the fuel filter. most probably still the original one.

Post by **misha** » 12 Oct 2018, 13:29

Clemens wrote: 12 Oct 2018, 11:11 ... and maybe replace the fuel filter. most probably still the original one.

That's is NOT good....it should be replaced between 50-100k km.
That's how i'm doing it.

Post by **misha** » 12 Oct 2018, 13:35

Clemens wrote: 12 Oct 2018, 10:08 ...edit: what's left feels basically like small misfires at steady rpms between 2 and 3k. Snooth under boost, alright when getting off the gas

I missed this on previous reply...are turbo models have intake air temperature sensor(IAT sensor)?

If not....i'm guessing that you have small vacuum leak somewhere.

I'm assuming that you don't have DTC stored or pending.

Post by **Clemens** » 12 Oct 2018, 14:41

No CEL. I had one showing a long term fuel trim issue when I bought it 2 years ago. After deleting it, it never returned. I searched for leaks thoroughly, couldn't find any. Maybe around the fuel injectors. would it be safe to spray the fuel injector seals with brake cleaner?

Post by **misha** » 12 Oct 2018, 15:19

I'm not sure about brake cleaner onto injector's o-rings.
What about IAT?

Post by **Clemens** » 12 Oct 2018, 15:42

from what I have read only cars 99 and up have that sensor. i will doublecheck tomorrow and try to read if any codes are stored even though no cel is on

Post by **misha** » 12 Oct 2018, 15:50

Being a '94 you will have just obdI diagnostic ports under the hood.

Some codes will not turn on check engine light but they will be stored in ecu fault memory.

Post by **Clemens** » 13 Oct 2018, 10:45

no codes stored in A2 (fuel system) and I can't get a signal from A6 (ignition) from the blinky box.
the lighter the throttle input, the worse it is. gotta look for vacum leaks again

Post by **misha** » 13 Oct 2018, 11:21

If fuel filter isn't replaced recently,like you said....i would replace it first.
What about spark plugs...being a turbo car....are they properly gapped?It is pretty important for turbo engine.
Ignition ecu should be also scanned for codes...could be that there is a problem...somewhere...and CEL being OFF doesn't necessarilly mean that there are not codes stored.
Maybe IT is the source of the problems you're experiencing.
That said....not being able to communicate with it....could be that there is a problem.

Post by **Clemens** » 13 Oct 2018, 11:30

plugs are new volvo, gapped correctly. maybe ignition wires. the ones on my 95 na went bad after 19 years, the ones on my 96R after 20. in this car they are from 94, one being a different length, looks like from the junkyard or sthg.