SureTrack Users General Discussion

[Witsend]

Headlight door actuator ?Maybe a 90s camaro or vette?

[sbreland73]

Euro crankcase pressure regulator, probably leaking vacuum. Looks like VW/Audi. Could be found on BMW.

[Witsend]

Euro crankcase pressure regulator, probably leaking vacuum. Looks like VW/Audi. Could be found on BMW.

Good call , Yeah kinda does look like a overpriced electronic Farfig kanuegen valve or a over complicated DISA valve that certainly gonna sludge up the head over time.;

[greasybob]

crank case pressure regulator it is. the vacuum readings were taken at the dip stick tube. I believe that this part also acts as the crankcase ventilation system. The symptoms are rough idle and high oil consumption. I thought that the 2 inches of vacuum with the new part installed was still a bit much.

[greasybob]

This is kind of interesting. I never seen this before that I can recall. It's an A/C compressor from a 2013 Kia Optima with no clutch. It has a solenoid that is operated by the A/C control module. I guess it's in bypass mode until the A/C is called for then it is closed to allow the pressure to build. I think that it is duty cycled controlled. When I was first diagnosing the inoperative system I had the power wire to the solenoid back probed and noticed it first was at 90% on then went to 100%. At first I thought that maybe the expansion valve was stuck open but replacing it made things no better, no pressure. So I replaced the compressor. Got pressure and cold air now. The benefit to this type of system would be the module could control the work load of the compressor by monitoring the high side pressure. The down side would be that everything inside the compressor is always turning. Maybe premature wear and more rotating mass. I tested the solenoid once I got it out. It draws about 800 milliamps but I'm not sure if it's closing.

[sbreland73]

Hey Bob, here is my thought on these variable displacement compressors = all a/c systems stay lubricated by operation of the system, as in the freon carries the oil through-out the system. During winter months, vehicle owners obviously use the a/c less, so the oil tends to collect in the lowest part of the system, leaving the rest to "dry" out. Also, the intent was to reduce or minimize the feeling the driver had when the a/c kicks in, especially in smaller engines. The newer VD systems actually pump small amounts of freon and oil through the system, regardless of of command. This valve you speak of controls the amount of freon that the compressor pumps through the system, to regulate pressure. You are correct that this valve is duty cycled. The theory is that there is less "shock" on the compressor during engagement in the "on" command from a clutch, so no wear there. They can add trickiness to the diagnostic procedure, but as long as you can monitor "command percentage" with a scan tool, or the duty cycle with a scope at this valve, to determine if the the HVAC is really calling for max cool, then you can determine if it is compressor or expansion valve failure. VW/Audi and Ford have lots of issues with these compressors. Typically when these types fail, you have near equal pressures in the high and low side of your gauges, or little difference. Be wary of the aftermarket too, as they tend to use cheaper, less reliable displacement valves than the OE, which in most cases are not that great to begin with.

[STURNER]

GMC Terrain Dual sump fuel tank

2014 Terrain 4cyl. Customer is a used car dealer that says fuel gauge stops at 1/4 tank and stays there until it runs out of gas. I dropped the tank and removed both tank units and checked resistance and gauge sweep. Both checked good. Installed both units and applied voltage and ground to fuel pump. It pulled from the primary side until it ran out of gas and left the secondary sump full. Customer provided both tank units used. Tried again with the same result. I can't find any info on what controls when pump pulls from secondary sump. Does it pull from both at the same time? Does the FSCM module call for the fuel pump to switch sumps? Is there a solenoid or switch inside the fuel pump module? Where is this info found? Posted on IATN as well.

[Witsend]

Used car lot rebuilt wreck?

I pulled up a wire diagram for 2014 Terrain with 4 cylinder and it doesn't even display dual sump fuel pump set up. I would take a picture of the option code sticker call the dealer with the VIN # and have them determine if it has twin fuel pumps and if the ECM and the fuel pump driver modules in the vehicle are correct.

[greasybob]

So you tried two different units and got the same results ? Is the cross over tube hooked up ?

[greasybob]

picture ? Maybe line has leak or is kinked or Oring missing ? My experience with collision vehicles is that a half tank of gas sloshing around can do some real damage to the pump assemblies. Bend and break things.

[STURNER]

Doesn't have two pumps, just two fuel sending units. The pump and gauge float is on the right side with the hose that extends to the left side unit that has another gauge float. Yes I replaced both units with ones from a salvage vehicle that included hose. I don't know if it determines fuel level on the average of the two gauges or if one is the boss over the other. I would think it would pull from both sumps at the same time since I don't see any controls for switching to the left sump but two setups have both left the left sump full. Thank you for all your time.

[Witsend]

Suck , Squeeze, Bang , or Blow let us know what you did to fix the flow

[greasybob]

I want to know too. if it only has one line running to the other side it must have some system of check balls or valves so it can draw from both sides and not suck air if one side runs dry.

[Trindaddy]

2014 Terrain 4cyl. Customer is a used car dealer that says fuel gauge stops at 1/4 tank and stays there until it runs out of gas. I dropped the tank and removed both tank units and checked resistance and gauge sweep. Both checked good. Installed both units and applied voltage and ground to fuel pump. It pulled from the primary side until it ran out of gas and left the secondary sump full. Customer provided both tank units used. Tried again with the same result. I can't find any info on what controls when pump pulls from secondary sump. Does it pull from both at the same time? Does the FSCM module call for the fuel pump to switch sumps? Is there a solenoid or switch inside the fuel pump module? Where is this info found? Posted on IATN as well.

Hi Shane. This system has 2 separate, independent fuel level inputs to the ECM though they do appear to share the same low reference via ECM. I suspect the ECM uses both signals along with its own strategy to determine what is left for fuel. It then sends the data to BCM and it passes the data to the IPC. The single jet pump draws from both sides as determined by the size of the orifice leading to both. If only the fuel on the pump side lowers I suspect something is blocking the line to the other side as another has suggested on IATN.

I once had a Kia where the pump housing broke thereby wasting the suction to one side or the other (can't recall). I suggest you start at the pump and verify you have unrestricted passage to other side. If anything like an AWD Volvo, it can be very frustrating to properly feed the tube over the hump. Wish you luck.

[DoctorD907]

2014 Terrain 4cyl. Customer is a used car dealer that says fuel gauge stops at 1/4 tank and stays there until it runs out of gas. I dropped the tank and removed both tank units and checked resistance and gauge sweep. Both checked good. Installed both units and applied voltage and ground to fuel pump. It pulled from the primary side until it ran out of gas and left the secondary sump full. Customer provided both tank units used. Tried again with the same result. I can't find any info on what controls when pump pulls from secondary sump. Does it pull from both at the same time? Does the FSCM module call for the fuel pump to switch sumps? Is there a solenoid or switch inside the fuel pump module? Where is this info found? Posted on IATN as well.

There is a baffle in the tank which can come loose (especially during a collision) and prevent the sender from falling below 1/4 tank and lower. Did you take a close look at the tank baffle? There is usually a sloshing noise during braking that accompanies this issue.

DrD