1998 v40 t4 Loss of power, then total stall [RESOLVED]

[def420]

The Volvo V40 voes.
My first post, but been lurking for a while, sucking all that invaluable information, from you fine gentlemen :-] Im from Denmark, so English is not my native tounge, so please bear with me .

Bought a 1998 Volvo V40 T4 (phase 1) with manual gearbox, this may. It drove perfectly and, we even took it for a 3000 km run, to the south of France, and back again. All was great, and i fell in love with the car.

Back to reality. Last 4 weeks, its been loosing power rapidly, and all came to an end, 2 weeks ago, when i filled it up with gas, and the car simply refused to drive. It would start (wery rough, rough idle - keep feeding with gas pedal, or total stall) but couldnt summon the power, to even start up from first gear. Left the car i vein, but had to go recheck later that night, and managed to get it going all the way home - limp home mode. Couldnt get past 2500 rpm, misfiring, lumping, coughing and so on. Lambda came on, and it threw a code P0444 (evap).

Went to workshop, and started replacing parts. Finished job, and now the car started up, ran for about 2 mins, then went into a comatic state, with total powerloss, funny unburnt fuel smell, no rpm what so ever, and finally died totally. Again.

Checked the battery, it said 11,9 volts (may be to low??) And it threw a P0172 code. On wednesday, im replacing the two lambda probes, the MAF and rechecking ALL the vacuum hoses. Found out that my one coil was cracked, and the HF cables was hard as rock, replacing them allso.

So far the car has been a nightmare. Ive thrown those dirt cheap original Volvo parts in, as where it my hobby to pour money into holes :-]

Getting Vida/Dice up and running allso, but afraid the 1998 models, arent Vida/Dice compatible, but need to go the Vol-FCR way.

So far ive changed (including job on Wednesday) : MAF, Spark Plugs, TCV, Coil, HT cables, Canister Purge Valve, One-Way valves on the vacuum line to CPV, O2 sensors. Brand new Mobil1 full synthetic oil in engine, Original Volvo oil in gearbox.
Allso changed the Fuel-Filter and Fuelpump.

My thesis is that, the front O2 sensor is bad, causing the ECU to cut off gasoline, thus making the engine not able to run. Or maybe my Cat has burned down, but dunno how to check :-[

Help or thoughts are deeply appreciated, as the next thing is, to have a professional workshop look at it, and if its too expensive, ill take it out and shoot it .



Christian

[matthew1]

Welcome to MVS, Christian! Your English is good.

P0172 = vacuum line most probably.

(A front O2 sensor going bad will cause the ECU to move more gasoline into the engine, not less.)

[def420]

Thanx a million for your reply. Makes sense, that a failing O2sensor would "drown" the engine, thus putting too much fuel into chambers, and giving med the smell of unburnt gases.
Is there any way to check if cat is failing??

[matthew1]

The cat will fail eventually after constant "rich" conditions. Your Volvo will throw a code when/if that happens, or your Volvo will fail an emissions test.

[def420]

Could a failing / meltet cat, cause the engine, to eventually drown in its own gases?? I mean, if the cat is totally melted down, the system wouldnt be able to breathe properly (getting the exhaust gases out of the way) , and cause the total stall on my engine ??

[matthew1]

I don't know. Try a search for "clogged cat" https://www.matthewsvolvosite.com/search ... &sa=Search

The P0172 points in a different direction.

[def420]

Once again, thanx for replying :-]

Think i forgot to mention, that upon inspection, the HT cable for cylinder 1, wasent touching the spark plug. So it might have been running without a spark on cylinder one (for god knows how long). Couldnt this put a lotta unburnt gasoline through the cat, and eventually destroyed it? I know the P0172 suggests a vacuum defekt, and im going to check again. Reason for me being so curious about the cat, is that ive been having funny smells, in the car, and the cyclus, with engine running good for 10 secs, then starting to deteoriate into total stall, makes me believe the cat is clogged up, and the exhaust gases is killing the engine.

Keeping fingers crossed, and giving it a thorough check in the morning.
Will keep you posted about progress. in the meantime, ill browse this fantastic forum :-]


Keep The Faith

[matthew1]

So it might have been running without a spark on cylinder one (for god knows how long). Couldnt this put a lotta unburnt gasoline through the cat, and eventually destroyed it? I know the P0172 suggests a vacuum defekt, and im going to check again. Reason for me being so curious about the cat, is that ive been having funny smells, in the car, and the cyclus, with engine running good for 10 secs, then starting to deteoriate into total stall, makes me believe the cat is clogged up, and the exhaust gases is killing the engine.

Yes, raw fuel going downstream from the engine will certainly kill a cat convertor given enough time.

[def420]

UPDATE : No luck yet, getting the car started. Changed out a lotta items, but to no avail. Car vouldnt rev up.
So i went through the trouble, of rechecking EVERYTHING again. Checked every single vacuum hose. Checked all gaskets, checked all fluids, checked turbo and so on. Finally I decided to check the fuel rail. Didnt pay much attention to this, as the fuel pump and filter, was just changed recently. Load and behold, gasoline pressure in the injection rail, was only 1 Bar!! Thats way too low, if im correct.
So: could the symptoms on the car running all fine and dandy in idle, but totally dying when i try to rev it up, be caused by too low pressure in the fuelrail??

Is there a sure way to check the pressure valve allso (the little thingie with the vacuum hose, connected to the fuelrail) .I mean, mine was just straight flow through, shouldnt there be a sort of regulation via the valve?


Thanks for any input/thoughts would be deeply appreciated :-]



Kind regards
Christian

[matthew1]

I'd say it's time to replace the rail and the valve with known-good ones.