Don't get me started on that "proper" parts thing again. While Volvo's love Volvo stuff I don't have any problems with my MSD fired AC Delco Platinum plugs, Oreilly cap, rotor and wires. It's not the cheap 1 yr economy stuff, as I get the better or best grade. It seems to be holding up just fine for near 50K now.

But the cars came with standard champion copper core plugs from the factory so any brand copper core should be fine you just need to check and change them more often.
Some people have complained that platinum plugs don't work in the Volvo but I'm not sure if it's just their personal preference or prejudice as I haven't had a problem with them on this engine or other non Volvo engines I've upgraded to platinum plugs.

 

I am not new to bosch systems at all. Like I said earlier I come from VW/Audi. Mostly Im a digifant fan but Ive had my share of motronic also. Its the same really. The sensors and theory is the same. Im not convinced that there is not a difference in conductive quality within any of the components generic vs oem. I am also not convinced that although there may be conductive differences between parts, cars with generic parts will fall on there faces like mine. I have increased my fuel economy from 17mpg@ 65mph to 19-20 mpg with generic parts. The gains are there I just haven't fixed the actual problem. Im not getting a dtc so im headed for wires tomorrow if anything is open. I still feel like these are tune up items and my real problem is an electronic component. I feel like I have ruled out the maf and although I haven't checked the cts my experience tells me its good. Ive had bad cts on Volkswagens and there is always a cel. As far as the thermostat goes. I will check the temperature of the coolant when the thermostat opens for the first time tomorrow.

What about generic 02 sensors? Keep in mind I have limited resources out here in the desert. My wife and son will be using this car starting Tuesday while I take a rental car to and from the site im working at. My main concern is reliability for my family when they trek into the desert to hike and climb.

 

Auto parts stores are open tomorrow and as for O2s, they came with Bosch and I know oreilly and autozone stock Bosch. You can order a Denso but they likely wouldn't have one in stock. I really don't know of a "generic" brand of O2

You have to remember with a CTS that if the coolant is 100 degrees and the CTS is getting out of range and it's actually reporting 80 degrees to the computer the computer isn't going to call it a liar and trip the CEL as the CTS is still within operating parameters. That is where it can go too rich or too lean and be "under the radar". It can cause a problem but not look bad to the computer. Usually you'll only get the CEL if it fails completely or it's a newer car with both a coolant temp sender and a cooling fan switch and the computer can compare the two.

 

Well, my theory is, if you HAVE A PROBLEM go at it with what came in it to rule it out. I remember like it was yesterday, installing some after market plugs in my red block Volvo. My gas mileage dropped 30% in 1 day (from a solid 24 mpg to a sad 17 mpg, while running smooth as a top). Continued for 7 days so I pulled them and dropped some Volvo plugs back in and my problem was solved. When it comes to gas prices at $4 per gallon, you don't have to tell me twice.

There is a chance that the timing is off as well.

 

I am new to volvos, but here's one data point on the O2 sensor: I am getting a 22mpg around town with a 94 turbo wagon that's probably never been tuned up in its life, and the O2 sensor is dead as a hammer. It's open loop all the time.

I am afraid to change out the O2, I'm afraid the gas mileage will get worse.

 

A second thought - I wonder if you've got air leaking out under boost conditions. That would make the car run rich.

 

firebird parts, that's the beauty of obd1 cars. Unfortunately Im rocking an obd2 turbo wagon and the 02s mean so much more. The losing pressure under boost theory is not a bad one. I have explored this however. I installed a boost gauge while in some small town in Missouri. The car holds steady vacuum at all speeds that are applicable and the boost builds as it should. I also have a vacuum pump and gauge that I used to test the system. The only thing I haven't done is smoke machine which isn't off the list. This morning I ran up to the store and the car made a solid 8 psi but wouldn't build anymore because the engine bogged and rpms were limited.

Last night in my research I decided to go ahead and buy a Bluetooth dongle for the obd2 port and run an app that has sensor monitoring and data logging on my phone. My oscilloscope will be here tomorrow and Ill tap into the 02 wire and quickly rule them in or out. The Bluetooth dongle will be here Wednesday and ill be able to see pretty much everything that I can only speculate. It seems one of the people working on Volvo binary has worked with these Bluetooth adapters running elm327 and they work well. At a total investment of $15.00 its a good buy and worth the wait.

 

That's a good point. Ill run some tests on the coolant temperature sensor when I get my scan tool. Im assuming that if the cts is saying 150 and I have 150 degree coolant then its good. It ohms good but I feel like that's a vague parts swapping test and without a good scan tool Im blind.

 

I appreciate all that have input to the situation and I'm certainly not blowing off the plugs and cap. I am just not going to replace them until I have exhausted all other diagnostic efforts since I have already paid for them and used them. The timing being off would lead me down the bad cps or maybe a flakey knock sensor. I guess there is the distributor being flawed in some way and the belt jumping a tooth on a camshaft in the worst case scenario section. Any suggestions on how to rule this out. I have already tested the cps and used contact cleaner on all of the plugs throughout the system. I may redo the grounds on the engine today just to be super thorough.

 

Has anyone on here ever tried this app.
OBD DROIDSCAN PRO - Free download and software reviews - CNET Download.com
I ordered the dongle today. I'm going to try to make it to Sand Diego next weekend time is getting short. Im hoping to get this knocked out before that trip.

 

tonight I drove into the mountains. the car did pretty good. I was getting @32mpg at 75 with a light foot on flat ground. but when I kicked I down into passing gear it just bogged. So far oreilly and autozone don't have wires in stock. napa and car qest were closed so ill have to check with them tomorrow.

btw I did the grounds today and it made a big difference. Im still not there yet though.

 

I pulled my fuel pump out today and foud out the the PO had installed a replacement pump and there was no strainer on it. I had to do a fuel filter after dropping the tank to replace cracked evap hoses and I had to replace the filter again yesterday. I have done stage zero all the way minus the pump. My boost is up to a solid 9-10 psi and everything has been gone over multiple times. I am still losing power under load. Today I put the fuel pressure guage on it again and as I raised the rpms the pressure dropped. I finally have hard evidence against a part failing but I have some questions now.

If I plan on improving performance after Im done with all of this stage zero repair will it hurt me to do a walboro 255 pump while im at it. Also how do I verify without a doubt that the evap solenoids are working properly so that I know Im getting proper venting I the tank. Also what would happen if there was no venting at all. Referring to fuel pressure that is.

 

These cars are sensitive to CEL's. If a valve doesn't work, the car will let you know.

Not sure about the pumps.

 

If the pressure is dropping as you raise the RPMs it's likely the pump is damaged and isn't capable of supplying enough volume to the injectors and so you see the pressure dropping. That or you have a restriction someplace between the pump and the fuel rail and it's able to hold pressure up until the engine is calling for more fuel that can get past the restriction. You might want to pull that brand new fuel filter and try to blow through it just to make sure some crud didn't already impair it's ability to flow enough volume.

The car doesn't care what fuel pump you put in a stock engine as long as it can supply at least the same amount and pressure as a stock pump.
Any excess a pump makes just gets sent back to the tank. Unless you get some monster that pushes more fuel than the return line can handle, not likely

Stock Volvo pump, stock aftermarket pump or high performance 255lph / 67 gph Walbro and the car will run exactly the same.

The difference is that with the higher output Walbro or some other brand you have more fuel available should you start to modify the engine and NEED more fuel delivered to the injectors and into the engine.

Stock specs on fuel pump:
Maximum Free Flow Rate (gph): 50
Maximum Pressure Range (psi): 100
Minimum Free Flow Rate (gph): 40
Minimum Pressure Range (psi): 80

If it can't do the minimums above, it's bad even if it's working.

 

Ok last night before buying a pump i ran the fuel preasure guage again. The PO spliced a piece of rubber hose on the supply at the pump and the quick release is gone. I put the guage there and read directly off of the pump. It idles at 42 and raises as i goose the throttle. I moved the guage to the rail and it read 38 and when i goosed it it woul go up to 40 and then drop to 38.

I removed the fuel rail and made sure it wasnt blocked. I blew out the lines between the pump and filter and filter and rail. I reinstalled everyrhing and checked carefully for o ring leaks on the injectors. I noticed that the clamp on the vacuum line for the pressure regulator was loose so I replaced it. I did another pressure test at the rail and the results were unchanged.

I pulled out onto the road and rolled into the throttle and the car took off surprisingly quick. It really pulled hard and I was far from prepared for it. I checked my torque data and everything looked good so I played for a few minutes.

Now my question is what should i do about the fuel pressure situation. Could it be the restriction in the line from where the PO spliced the broken supply? The car hasent run this well since ive owned it but I have a feeling it could do better. Ive always owned VW and Audi. I am very surprised at how hard this car pulls under boost and stoked to own the car I dreamed of owning before my VW addiction a turbo wagon.

 

Those were the specs on the fuel pump if you were testing it on a bench. IT"S NOT the operating system pressure installed and tested while running.


From the "book"
FUEL PRESSURE
Fuel Pressure
1) Before disconnecting, cover fuel line connector using shop
towel to absorb any fuel spray. Connect Fuel Pressure Gauge (5011)
between fuel line and fuel rail. Seal free end of hose using Plug
(5266) or use Fuel Drainage Unit (981 2270, 2273 and 2282).
2) Lift cover on central electrical unit located in engine
compartment and remove fuel pump relay. See Fig. 1.
3) Connect a jumper wire between relay terminals No. 1 and 3.
See Fig. 2.
4) Turn ignition on. Fuel pump should start. Fuel filler
cover can be removed to determine whether main pump is operating. Fuel
pressure should be about 43.5 psi (3.06 kg/cm ). If pressure is too
low, pinch return hose by hand and check whether pressure rises. DO
NOT allow pressure to exceed 86 psi (6 kg/cm ).
5) If pressure rises rapidly, pump and lines are okay.
Replace pressure regulator and recheck line pressure. If pressure
rises slowly, fuel filter, fuel pump strainer or fuel lines are
blocked. If pressure does not rise, fuel pump is probably faulty.
6) If pressure is too high, remove jumper wire between relay
or fuse terminals. Remove return hose from pressure regulator. Blow in
pipe. Remove vacuum hose from pressure regulator. Blow in pipe. If
both hoses are open, pressure regulator is defective. Replace
regulator and recheck pressure.


Soooooo, your pressure sounds like it's pretty much where it's supposed to be. Remember the regulators function besides regulating a steady pressure is to also raise that fuel rail pressure as the vacuum drops. That's why there is a vacuum line leading to it and it's to have more fuel at higher RPMs (ie lower vacuum).


Remember too much pressure can be as bad as too little !!

 

You will get a more accurate value on what pressure the engine is "seeing" if you have a screw on fuel pressure tester and take that reading from the fuel rail itself.

 

Have you replaced the fuel filter (big bosch silver can) and installed a strainer onto the fuel pump as yet? I don't care how new that fuel filter was, if you haven't replaced it since you discovered you had no strainer on fuel pump intake, it needs to be renewed. A partially clogged fuel filter is likely causing your pressure drop between the pump and rail.

Also, even if that pump has correct pressure now, its life has been shortened by running it w/o the strainer...

 

I guess I failed to mention that I did buy a strainer for the pump and installed it at the time of purchase. I could and should take stock in fuel filters at this point and I want no doubts about its health. My question is could I do a timed flow test just past the filter to check it off without just replacing it? I did replace it three days ago and used a flashlight to check the tank cleanliness when I discovered no strainer. It was perfectly clean in the bottom of the tank. That's not to disregard the advice in any way. I also did the return hose pinch test when testing the pressure at the rail with a screw on type tester. The pump past that test with an almost instantaneous rise to 70 plus psi.

 

Also just to clarify. Starting from page one of this thread my entire issue was caused by the loose clamp on the FPR vacuum line. No rising rate fuel pressure under boost because the boost was causing a leak in that vacuum line. My stage zero is solid now minus the pump pressure questions. If anyone agrees that a filter that passes a flow test is good Ill do that and call it good or bad. Also I haven't found a spec for what the pressure measured at the rail should be at idle. I assume that the book instructions are written to test the pressure minus the regulator inline. I could also test at the supply fitting before the regulator and that would include the filter and subtract the regulator. Any thoughts.