MyBrickIsSlow Posted October 2, 2016 Report Share Posted October 2, 2016 I have owned my coupe for several years now. I purchased it in a neglected state, replacing everything from panels to a new engine. I have always wanted a coupe, but this one is beginning to change that for me. I have double the cars value invested, and have worked out every major issue except one... The car has had all the symptoms of a failing ETM, idle surge, rough acceleration, and stalling, since day one. Keep in mind there are no ETS light and no codes. The ETM has been swapped, I have tried a new cantactless sensor, and finally a brand new unit. All with similar results... none. I have followed the flow chart in every direction (its leads to MAF if followed correctly). Ignoring the actual path of the flow chart and testing every item has yeilded nothing as well. The voltage read out at the connector is 12.** V , same as battery. Ground is clean... ALL grounds cleaned and checked. MAF has been swapped. Adaptives have been reset at every step. EDIT: software update at the dealer as well. That being said. Last night I worked on troubleshooting more, and reset the adaptives again. Now the car will start, idle up to 1500rpm and then immediately stall. I can force the car to rev to 4000 rpm, but no higher, by holding the pedal to the floor while cranking but if the pedal it depressed the car will stall. I am at my wits end with this particular car. Link to comment Share on other sites More sharing options...
venderbroeck Posted October 2, 2016 Report Share Posted October 2, 2016 Does it sound lean? Maybe the fuel pump or fpr is failing? Do you have someone nearby with a dice unit that can do the sweep test on vida? Link to comment Share on other sites More sharing options...
MyBrickIsSlow Posted October 2, 2016 Author Report Share Posted October 2, 2016 I no longer have access to vida/dice. However I can check fuel pressure the old fashion way. Thanks for the suggestion. I will get a gauge on it and post the results. Link to comment Share on other sites More sharing options...
Ihatespeedbumps Posted October 3, 2016 Report Share Posted October 3, 2016 I second the ETM test on VIDA, would be invaluable to learn the results. Link to comment Share on other sites More sharing options...
gdog Posted October 5, 2016 Report Share Posted October 5, 2016 On 10/2/2016 at 1:15 PM, venderbroeck said: Does it sound lean? Maybe the fuel pump or fpr is failing? Do you have someone nearby with a dice unit that can do the sweep test on vida? Fuel pressure regulator would be my guess too; when they went to return-less fuel system in '99 MY, the first few years had lots of problems with these.. but again, just a WAG; ck the fuel pressure at various loads if you can i.e. safely secure the fuel pressure gauge and take it for a drive with it taped down to the windshield so you can read it; log what you see. Link to comment Share on other sites More sharing options...
MyBrickIsSlow Posted October 9, 2016 Author Report Share Posted October 9, 2016 Correct me if I am wrong but I was under the impression that this car only has a fuel pressure dampener, and not a FPR. I was unable to find a gauge locally with the correct shraeder valve adapter. But while trying to work that out, I found I had almost no pressure at the rail itself. I checked the shraeder at the rear of the filter and there was substantially more pressure. I changed out the fuel filter and tried again. Better pressure but still far too low. I had a spare fuel pump assembly laying around and swapped it in. The engine has smoothed out substantially and I was able to rev it at 1500 rpm until it was up to temp. (It would still stall if I let off the pedal) Once up to temp it idles on its own. However if you touch the pedal the car drops rpm almost to the point of stalling. If the pedal is rapidly pressed and released you can get the engine speed up without falling on its face. But once load is applied it will stall or buck uncontrollably. I have to admit I am at a loss at this point. Will be looking for a tester with the proper shraeder adapter. Link to comment Share on other sites More sharing options...
gdog Posted October 10, 2016 Report Share Posted October 10, 2016 Well watching how much fuel comes out of the schrader valve is hopelessly inaccurate in determining its pressure I'm afraid; you'll need a fuel pressure gauge that can handle up to 80psi or more. I suspect you have a fuel pressure issue, but no-one will know for sure until you (or someone) applies a gauge and takes a look, per previous posts in this thread. I don't own a '99 or later car, so I am no expert on these vehicles, but I know they went to return-less fuel system in 99 MY. This link explains what that is generically: http://www.aa1car.com/library/returnless_efi.htm Again, I am not sure exactly how volvo implemented "returnless" but from my limited research just now, I'd say it evolved over the years starting in 1999. The system usually has a fuel pressure regulator in the system somewhere; I assume it's in the fuel tank. Some of these also had fuel pressure sensor in the rail, but I don't know if they did in 2000 MY. From what I've read the fuel pressure sensor was a major source of driveability issues through the first half of the 200X MYs, to the point that there were recalls about it. But back to the diagnosis; this is all just talk if you don't have a fuel pressure issue, and you won't know that until you measure the fuel pressure.. Link to comment Share on other sites More sharing options...
MyBrickIsSlow Posted October 10, 2016 Author Report Share Posted October 10, 2016 gdog. I am aware how "hopelessly inaccurate" my method of checking the fuel pressure is. But i thought that went without saying. I am still learning the 99+ models as well. I currently own an 00 and an 01, and am trying my best to deal with the problems on my own. It has been my understanding that these cars use an algorithm based on several sensors, not based on fuel pressure, to determine voltage duration and intensity to the fuel pump. This is the reason a bad ets will keep the car from starting. Without the temp input into the algorithm the ecm won't add the extra fuel for a cold start. I have never read this in plain print but reasoned this to be the case... But lets assume its not a fuel issue for a moment and let me ask you what else could cause the current symptoms? I will have several days before the new tester arrives and would like to explore other options of possible diagnosis. Link to comment Share on other sites More sharing options...
Ihatespeedbumps Posted October 10, 2016 Report Share Posted October 10, 2016 Fuel pressure at idle should be around 4 bars. I wouldn't want to speculate any diagnosis until we have confirmed proper fuel pressure. As a side note is there any history of the fuel pump relay ever being changed? Extremely high rate of failure. Link to comment Share on other sites More sharing options...
MyBrickIsSlow Posted October 11, 2016 Author Report Share Posted October 11, 2016 I have not located a spare yet. I have all of my extra parts in storage and have looked twice for the relay. This is how I found the extra filter and pump assembly. Link to comment Share on other sites More sharing options...
Ihatespeedbumps Posted October 11, 2016 Report Share Posted October 11, 2016 Unless the date code on a used one is relatively new I strongly suggest using a new one. Given the high rate of failure it's practically a maintenance item on these cars. Link to comment Share on other sites More sharing options...
MyBrickIsSlow Posted October 16, 2016 Author Report Share Posted October 16, 2016 I had most of the afternoon to work on the coupe today. I found the cause of the start and immediately stall issue. At some point while changing MAF housings I managed to pull the intake tube partially off the compressor housing. I am not sure why this didn't throw a code for MAF low input. But now it will start and idle as it should. However, it still has a stumble when a load is applied (in any gear) and engine speeds will still drop well below idle every time you take the load back off. It will also stumble hard when you let off the gas with it still in gear. If it was not clear before the coupe is a HPT manual car. EDIT: I did try a different fuel pump relay with the same results. And still have not checked fuel pressure. Link to comment Share on other sites More sharing options...
MyBrickIsSlow Posted October 28, 2016 Author Report Share Posted October 28, 2016 Purchased and installed a new Bosch MAF. And the car ran much better... At least long enough to throw a P1155 CEL. The turbo has needed a rebuild, and I ended up buying a new CHRA. I will be installing that tomorrow. Along with a new upstream O2 sensor. Link to comment Share on other sites More sharing options...
MyBrickIsSlow Posted October 30, 2016 Author Report Share Posted October 30, 2016 New CHRA has made a world of difference. All symptoms are gone minus the idle dropping below normal. I am going to assume the o2 sensor will sort that out. But I want to put some mileage on the car before swapping it out. CEL has not returned as of yet. Link to comment Share on other sites More sharing options...
MyBrickIsSlow Posted October 31, 2016 Author Report Share Posted October 31, 2016 I drove the car to work today, 60 mile round trip, and it through a code. P1172 I am finding mixed info on the causes, but o2 sensor is one. With the previous P1155 code being thrown i guess I will be changing the sensor. Any insight on the P1172 would be helpful. Link to comment Share on other sites More sharing options...
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