Alright to make a long story short I am a proud owner of a 97 volvo t5 that runs like a champ but has a few issues that I have just become aware of. First off the brakes are not exactly responsive with alot a play in the pedal even after bleeding and new rotors or pads. I assume it is an abs module issue but not sure if it is more. what would be a big red flag that it is the actuator pump and relay as opposed to the module?

Ironically the cel/abs light/ and traction control light seem to be either burned out or disconnected. Is there any way besides pulling out the cluster to check if the lights have been disconnected? Like checking a fuse or a connection point under the hood. I find it strange that along with those warning lights, the light that illuminates the clock & digital stuff (mpg, temp, average mph) is also burned out.

Lastly I have recently found a manual boost control that was hiding under the hood. This would trip the cel I assume, but what if you are pushing stock boost?

Thanks in advance!!!

 

When you say "play" are you talking about a soft pedal or excessive pedal travel ??
When the pads were replaced where the caliper pins cleaned and properly lubed with a high temp brake lube ?? Where the contact areas properly cleaned, scraped or wire brushed to remove scale and rust so the pads can smoothly follow the rotors ??
Who did your brakes and did they bleed all 4 ??
Was the master cylinder ever allowed to run dry ??

The manual boost control shouldn't trip a code as the computer has no way of knowing it's there and you are running at stock boost levels and no way of knowing if it's good or bad.

 

I did the brakes myself and I sure did all of the above but did not bleed all 4 wheels. Since I did not open the the brake system I did not have any reason to bleed the lines. Eventually I did bleed the front 2 just as a test to get an idea if that was the issue. If I saw that there was a worth while amount of air coming out either of the front I figured then I would fork out the $$ for either a pressure bleeder tool or pay for the service.


Master cylinder reservoir has always been full since I owned the car, but can not speak for the previous owner. As far as play it just feel to me that I shouldnt have to push the pedal that far to get the car to brake and the brakes do not bite like I assume they should. I think there might be a possible vacuum leak on the booster but not sure where the line comes and goes from. DO you have a diagram or something that maps out the location?

Thanks Also I want to unhook the manual boost control and hook up the original TCV. Do you think this is a good or bad idea? I have no clue the boost I am running, but hesitant to unhook the control since it has always been on my car. I figured the ECU has adjusted and fear a change back will cause problems with fuel mixture.

 

As for the CEL, when you turn the key to the run position before you start the car, does the lights light up? If not, you either have bad bulbs or bad cluster. It sounds as if you have done most things to rule out everything except the master cylinder.

 

Yea the bulb does not illuminate when car is in the on position. along with the abs, tracs, and service light. ****ing guy I bought the car off must have plucked them out.

 

You can pull the dash pad off to see if those bulbs were removed or have burned out. Chances are they are removed.

You can check the codes with the OBD-II port or you may have to have a real Volvo mechanic pull them if your reader wont. Keep us posted.

 

Yea that's what I figured. Not to mention the dash looked like it had been disassembled since the corners where a little loose and the wood panel is MIA. I figured an easier way to be sure it is out was to get it scanned. It pulled only 1 code and that being p0422, which I know is from a combo oil leak from a turbo line and most likely a rear main seal dripping down the exhaust. I did cheap-out and go to autozone for the free scan, but what I thought was strange is that the scanner did not pick up the cars make as volvo. It displayed as domestic US car.

Would that be because it is just a generic scanner, or possible an issue with the ECU? The guy at autozone looked confused and advised me to go to a full service mechanic to get it checked it out. I literally find something new everyday that this kid did to my car even after owning it for nearly a year. If anything though it re-enforces my opinion of Volvos being AWESOME cars since it runs so daum goood.

 

The P0422 is a rear o2 sensor code. Either the rear o2 sensor is bad or the cat is getting a little clogged. I had the code and could not get the sensor out. So I unplugged the sensor and the cel has not returned. Nearly 500 miles. SMH. I think the sensors only purpose is to monitor the efficency of the cat.

 

It's more likely due to the way that person went in to the menu. Most autozones use an Actron code reader and you can go in and do generic OBDII reading and they will print out the definitions off the parts computers or as in your case the person can try to enter your car. It should still pull up the correct code either way but my money is on the person trying to enter your car hitting a wrong button.

 

Not sure what your emission laws are but if my o2 sensor tripped for a real reason chances are I will not pass the exhaust test. Granted it gets rid of the cel but I do not even have one any way lol. I was reading online that someone tripped the same code and also had a slight oil leak near the back of the motor that would drip run down the exhaust causing it to burn up. The fumes made their way to cat and the o2 sensor would trip the cel due to it thinking the car is running to rich. I think that is what is going on with my car due to the fact that I also have oil that leaks down the back and is very close to the cat.

The cat looks to be in good condition and passed the rubber mallet test. I plan on testing out to see if the o2 is operating properly this weekend by monitoring the range of volts of the output wire with a voltmeter.

Quick question since you seem to be on top of your ****. I have a manual boost control and really have no clue where the psi is at other than how fast and far the needle goes in the white. Would you suggest unhooking the MBC and start using the orginal TCV? I am paranoid that this is going to **** something up since my car is running fine and its been with it awhile so I figured the ECU adjusted for it. I know it takes awhile for an ECU to map out once it has been reset and I just picture it frying if I switch out the mbc. At the same time I really want to maximize the life of this car and not knowing the PSI I am running could shorten her life.


THANKS in advance and sorry to ramble.......

 

Since the exhaust manifold, downpipe, cat ... have pressurized exhaust gas in them I'd have a had time thinking any vapor from an oil leak would get pulled inside.
I've seen some pretty strange things happen and odd things cause problems you wouldn't think they could but getting an exterior oil leak to cause a richening up of the exhaust .... really doubtful. Just my two cents.

 

Well I did not mean it gets inside the exhaust. An o2 sensor basically just measures the oxygen in your exhaust and compares it to the outside air. The problem is when it is measuring the external oxygen levels it is getting all the oil vapor which is externally burnt up on the cat. As a result the sensor is reading too much oxygen inside the exhaust compared to the outside. In other words it thinks the engine is running lean and the ecu adjusts by increasing the fuel consumption causing the car to run rich.

I also heard if the pcv system is gummed up it will cause blow back forcing oil to spew out where ever it can. I have this problem for sure, but was wondering if it is worth taking apart and cleaning or just replace everything?

Funny thing is after all finding all this out (from the cel to the o2 sensor) today I received my invitation to emissions.

 

Best of luck,may you prevail

 

Replace everything.

 

Yes, it definitely will and replacing it is the better bet. You can clean it and you will not know if you opened it up inside and it's working properly until you reinstall it and fire it up and by then it's too late !!

 

I could be wrong .........

 

Oxygen sensor - Wikipedia, the free encyclopedia

"The sensor does not actually measure oxygen concentration, but rather the difference between the amount of oxygen in the exhaust gas and the amount of oxygen in air."

it uses voltage to communicate to the ecu what is going on. Depending on the sensor there is a small vent either internally or a "breather" wire to the outside air. The difference in oxygen levels between the exhaust and outside air within the the sensor causes voltage to flow through the bulb. The greater the difference the higher the volts. The ecu reads the voltage of the sensor and will adjust the fuel/air ratio accordingly. More volts = too rich & vise verse.

 

From your wiki reference : In automotive applications the titania sensor, unlike the zirconia sensor, does not require a reference sample of atmospheric air to operate properly. This makes the sensor assembly easier to design against water contamination. While most automotive sensors are submersible, zirconia-based sensors require a very small supply of reference air from the atmosphere. In theory, the sensor wire harness and connector are sealed. Air that leaches through the wire harness to the sensor is assumed to come from an open point in the harness - usually the ECU which is housed in an enclosed space like the trunk or vehicle interior.

They are designed to be waterproof to keep out stuff that would corrode them like road salt. They aren't open to the air.
Seeing as it's designed to get that air from a break in the wiring and that it doesn't pump air I would find it hard to believe an oil leak and the burning vapors would influence the sensor BUT, stranger things have happened.

 

Yea I thought that was kinda hard to believe the gap between the wire insulation and copper would be enough room for air to vent. I was pretty much just trying to convince myself the issue was from my oil leak. I hate the fact that 1 code error could have 20 different problems that caused it. In my opionion it really kills the purpose of having all the systems checks and balances.

I know my cat is in good shape just based on its appearance and when I tapped it with a hammer I do not hear any broken monolith bouncing around. As much as it pains me to say it, I am pretty sure I have a large vacuum leak causing the motor to misfire. Anyone out there have a good strategy for finding it???? Other than covering my engine in carb cleaner.

The car does have a noticeable shutter at higher RPMs if I put the pedal to the floor from a dead stop. It idles and drives fine at regular rpms.