Need help diagnosing engine running rough

[SalvadorP]

Originally Posted by griston64

I cant remember to be honest. I got the hose and clips from Volvo dealer FRF Swansea

ah, ok. well, in the meantime I found them on amazon. I didn't know what they are called in spanish, so that's why I wasn't getting any results.

btw, I said goblin clamps but I meant "corbin". either way that's not how they are called in spain.

I was trying to find a diagram for the fk engine to count them, but all that pops up is the 94 US version of the car. I also bought the lenght based on those values, mentioned on the volvoclub faq. it says 4 meters of 4mm is enough, I bought 5. does 4 meters sound of? do you remember?

thanks,
salvador

[griston64]

Originally Posted by SalvadorP

ah, ok. well, in the meantime I found them on amazon. I didn't know what they are called in spanish, so that's why I wasn't getting any results.

btw, I said goblin clamps but I meant "corbin". either way that's not how they are called in spain.

I was trying to find a diagram for the fk engine to count them, but all that pops up is the 94 US version of the car. I also bought the lenght based on those values, mentioned on the volvoclub faq. it says 4 meters of 4mm is enough, I bought 5. does 4 meters sound of? do you remember?

thanks,
salvador

I think 5 meteres should be ample

Diagrams of turbo engines will be in here https://www.gcp.se/en/catalogues/mod...60-s90-v90-en/

[SalvadorP]

Originally Posted by griston64

I think 5 meteres should be ample

Diagrams of turbo engines will be in here https://www.gcp.se/en/catalogues/mod...60-s90-v90-en/

I didn't know there was a diagram in the catalogue. Gonna look for it tomorrow. Thank you very much.

[baggy798]

If the injectors are the original with 500000km on them, it's probably best to buy a new set!!

Could be the MAF that is giving you the rough running, I think they can go wrong and give issues even if they don't throw a code.

Have you blanked off the idle valve to see how it runs? I bypassed the stupid idle valve years ago as it used to idle at 1500rpm unless you came to a dead stop, so annoying in traffic.

[SalvadorP]

Originally Posted by baggy798

If the injectors are the original with 500000km on them, it's probably best to buy a new set!!

Could be the MAF that is giving you the rough running, I think they can go wrong and give issues even if they don't throw a code.

Have you blanked off the idle valve to see how it runs? I bypassed the stupid idle valve years ago as it used to idle at 1500rpm unless you came to a dead stop, so annoying in traffic.

Regarding the injectors. I have a volvo excell sheet with all the maintenance detailed, the original owner brought the car to the same dealership where he bought it every year. Anyway, that's one thing I can't find in the sheet as being replaced, but there are several spanish abreviations that I don't know what they are. What I do know is that virtually major parts of the car were at least once and several times in many cases. This was the type of person that paid the volvo dealership to do the MOT for him.
Anyway, maybe they are the original ones with 500k. But right now I can't swap them for new ones as that's a big buck.

MAF is also one of my top 3 suspects. It is not the original, in fact it is the third, oem and has less than 50k km. Having said that, I am ashamed to admit I once washed the engine bay carelessly and I might have soaked it. After that event it was the first time I noticed any misfires.

I did fiddle with the idle valve a bit. I cleaned it. My car was also some time ago idling high with that same issue of only dropping after a few seconds of coming to a halt. I am not sure if it stoped after cleaning the idle valve, but I haven't noticed it doing it recently. Anyway the impression I got was that it wasn't related to the valve.

I am mostly down to 3 factors, a faulty sensor, a faulty MAF, or injectors.
I should probably remove the injectors and make a visual inspection. The car had all gaskets replaced, block resurfaced and all that less than 40k km ago, so I imagine they at least cleaned the injectors.

[SalvadorP]

Not only did I broke the Y piece above the pcv breather again (ordered one from volvo, arrives tomorrow ), I noticed the top pf the pcv, the hoses, as far back as the T piece/valve that connect to the tube near the MAF, it is all very oily.

Does this mean the the MAF is probably dirty? Gone? Or something else worse? I'm worried about the amount of residue near the MAF, seen in the picture.

[IMG][/IMG]

[SalvadorP]

Is it at all ok to drive with the hose that goes from the Y nipple above the crankcase to... I really don't know where it goes, suppose the intake manifold?

I need to go get the new nipple tomorrow from the dealer and it's a bit far from the train station, so I was wondering if it would be safe to drive a few kms "without" the nipple.

[Laird Scooby]

Originally Posted by SalvadorP

Is it at all ok to drive with the hose that goes from the Y nipple above the crankcase to... I really don't know where it goes, suppose the intake manifold?

I need to go get the new nipple tomorrow from the dealer and it's a bit far from the train station, so I was wondering if it would be safe to drive a few kms "without" the nipple.

You need to trace the small bore hose from the flametrap/nipple back to the inlet manifold. Find the stub it goes onto and check it - chances are it's blocked solid. While you'e out, buy some caarb and air intake cleaner if you don't already have some - use this and an unfolded paper clip or small drill bit to clean out this stub before fitting the new flametrap/nipple.
If it's not blocked (i think it will be from what you've said) then find an old piece of small bore vacuum tubing and a suitable size bolt and put the bolt in one end and the short length of tubing on the stub to temporarily block it off.

Also find a piece of hose long enough to go from the oil separator/trap on the side of the block to above the inlet manifold if not a bit longer. If you sit the remains of your old flametrap/nipple in this and take it easy on your journey, you should be ok. You might want to simply fit the new one straight into the extended hose from the oil separator as this raises the amount of distance stray oil has to travel up the pipe before it can clog the flametrap.

As the engine will be sucking this side of the MAF it's unlikely that the MAF will be contaminated with oil/sludge, it's self-cleaning for the most part although you can clean it if it's really necesary. Once you've cleaned that manifold stub (have you ever cleaned the oil separator?) and refitted everything, especially if you leave the flametrap raised above the inlet manifold, you'll find it runs better anyway.

[SalvadorP]

Originally Posted by Laird Scooby

You need to trace the small bore hose from the flametrap/nipple back to the inlet manifold. Find the stub it goes onto and check it - chances are it's blocked solid. While you'e out, buy some caarb and air intake cleaner if you don't already have some - use this and an unfolded paper clip or small drill bit to clean out this stub before fitting the new flametrap/nipple.
If it's not blocked (i think it will be from what you've said) then find an old piece of small bore vacuum tubing and a suitable size bolt and put the bolt in one end and the short length of tubing on the stub to temporarily block it off.

Also find a piece of hose long enough to go from the oil separator/trap on the side of the block to above the inlet manifold if not a bit longer. If you sit the remains of your old flametrap/nipple in this and take it easy on your journey, you should be ok. You might want to simply fit the new one straight into the extended hose from the oil separator as this raises the amount of distance stray oil has to travel up the pipe before it can clog the flametrap.

As the engine will be sucking this side of the MAF it's unlikely that the MAF will be contaminated with oil/sludge, it's self-cleaning for the most part although you can clean it if it's really necesary. Once you've cleaned that manifold stub (have you ever cleaned the oil separator?) and refitted everything, especially if you leave the flametrap raised above the inlet manifold, you'll find it runs better anyway.

I was thinking of pinching the hose, but I guess the screw is a better solution.
Right now the nipple has the 4mm outlet broken of, so I have to close that hole too, so I can make it to the dealer and mount the new nipple.

Yes, I have cleaned the oil separator after I bought the car, about 20k km ago or so. I'm probably gonna clean it again. But I think you might be right, the stub might be blovked, or the hose itself. I brought the hose home with me cause the small nipple outlet is still inside, I'm gonna check it, since I didn't thought of that before.
Correct me if I'm wrong. This is stud/hose from the nipple is to release excessive pressure from the oil separator? And so if it's clogged it will make a strain onde the system, is that it?

[griston64]

Originally Posted by SalvadorP

I was thinking of pinching the hose, but I guess the screw is a better solution.
Right now the nipple has the 4mm outlet broken of, so I have to close that hole too, so I can make it to the dealer and mount the new nipple.

Yes, I have cleaned the oil separator after I bought the car, about 20k km ago or so. I'm probably gonna clean it again. But I think you might be right, the stub might be blovked, or the hose itself. I brought the hose home with me cause the small nipple outlet is still inside, I'm gonna check it, since I didn't thought of that before.
Correct me if I'm wrong. This is stud/hose from the nipple is to release excessive pressure from the oil separator? And so if it's clogged it will make a strain onde the system, is that it?

It's no so much of an issue on Turbo cars to be honest. The Y piece will be fine if you cleaned it 12k ago. I did my separator box after 18 months and all the pipes and box were clean as a whistle.

Even my non turbo 740 that actually has a flame trap was pretty clean.