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Everything posted by turckster

  1. Aftertreatment fuel psi should be what.... 90ish psi? What test is it that you can not perform that requires a special tool?
  2. All of these faults are voltage related. Fuse 38 powers the EECU, make sure it has battery voltage (12+ volts). Fuse 38 gets its power from the starter relay. Make sure all battery, starter and ground connections are clean. Checked the ground relay connections on the firewall as well.
  3. When you say dash unit do you mean the instrument cluster? If yes I would think the issue is the harness connector terminal. Either the 27a or 22b terminal is loose on the pin. If you are careful you can remove the terminal from the connector and carefully pry the contacts. The reason I say that is you tried this cluster in another chassis and it worked, correct?
  4. When you turn the heated mirror switch on you should have voltage at pin 87 at the heated mirror relay. When there is voltage at pin 87 there should also be voltage at pin 12 on the H/M switch (for the lighted part of the switch). If you don't have voltage at pin 87 (relay) then there is a wiring issue somewhere. You have verified the components(switch, inst. cluster, mirrors and relay) are ok. Measure resistance from pin 4 (switch) to pin 27A (instr. cluster), should be 0-5 ohms. Measure resistance from pin 86 (relay) to pin 22B (intsr. cluster). Wiggle the wiring to see if the resistance jum
  5. According to the wiring diagram, when the switch is turned on there should be voltage at pin87 on the heated mirror relay. The instrument cluster controls the relay ground circuit (pin 86 on relay). The instrument cluster may also have a heated mirror icon which may be why the switch power (pin 4) goes to the cluster plus it acts as a signal to turn on the relay ground. It possibly could be a feature that needs to be enabled through the dealer or using PTT2 if you have it.
  6. The fault SPN:3556 is for the Aftertreatment Hydrocarbon Doser or 7th injector. The FMI:4 is voltage below normal or shorted to low source--short to ground. Probable cause is faulty harness or 7th injector. On an MP8 the 7th injector wires run down the passenger side of the valve cover to the rear of the engine where the sensor to engine harness connector is. Its possible the 7th inj. wiring is exposed and shorting to ground or the injector is just bad. It will not perform a regen because the 7th inj is faulting.
  7. A common problem spot is the engine to chassis harness. I have seen them chafe on the harness support bracket mounted to the air compressor head and cause a short. There are a few other rub spots for that same harness in that area as well. Another possibility is the harness from the cab to the frame. If it is not properly secured there are tons of rub points for it also.
  8. The econovance was used on inline inejction pump engines to advance the injection timing mechanically. When the etech came out in 1997 it had an injection pump for each cylinder. The engine ecu used a cam position sensor and engine position sensor to determine TDC and adjust timing from there electronically.
  9. 99.9% of the time I just look in the fuel tank at the return tube and check for air coming out. Make sure the plastic cap by the fuel primer pump is not wet and if you have the 7th inejctor w/air purge "T" fitting, remove the air purge line. If, after idling for a while, you still have air in the return pipe you most likely have leaking cup(s). Rarely have I ever used the clear line kit. Yes, I got bit once. The 7th injector "T" fitting was bad and air was getting back into the fuel system from there.
  10. Check by the fuel hand pump on the fuel filter base, there is a little plastic cap. When you pump the hand primer does fuel bubble out around the cap? If so then replace the cap, it is causing fuel drain back and air in the fuel. If it is dry, remove the fuel tank caps and check for air in the fuel return. let the engine idle for 5 or so min. and then check. If you have a constant stream or big blobs of bubbles every few seconds then you more than likely have injector/cup issues. When the injectors are removed, if 3 or more injectors show leakage then it is best to replace all injectors a
  11. If he installed all EUP's without o-rings the engine would not start and would be full of fuel in no time. Plus, fuel would be running all over the right side of the block. I don't think I would be worrying about a 1/16" of an inch since so many things could affect oil level. Now 1/4" + in 1,000 miles--- maybe then I'd worry.
  12. Trying to remember since its been so long but I think what your talking about is an old design. Everything is the same as far as clutch brake adjustment. They used a spring loaded pad instead of a solid type to extend clutch brake life (?). Could be wrong as far as reason. Like I said, been a while since I've seen one.
  13. Since you will be replacing the egr valve you should clean the 7th inj tip. We use Berrymans B-12 carb cleaner and a soft nylon brush but any quality carb cleaner should work. I wouldn't swap the dosing module. As a 7th inj. starts to get dirty its efficiency drops, that is it's adaptive factor (as the eecu measures it). When you replace or clean a 7th injector you need to reset the "adaptive factor" to tell the eecu to re calibrate to new. On Volvo/Mack software (PTT2) it's under the "aftertreatment diagnostics" tab, not sure on other software. During a regen the 7th inj. is at 100% to keep
  14. Need more information such as year, vin, model and so forth. That will help in identifying what you have.
  15. Usually if the egr valve is ok the glove will expand a little but not pop. You will have some air in the fuel return when you start up an engine but it should go away in about 5-10 min. When not doing a regen the dosing valve will be at 100% to purge air--to keep the 7th inj. tip clean. Being under a load may have helped the regen to build temp but if its not happening during a parked or forced regen there is an issue. Many things will affect a regen form one reason or another, but not building temp is usually either a dirty/poor spray pattern on a 7th injector (adaptive factor percentage sho
  16. Your temps are slow to rise and never reach proper temps? is that correct? Problem could be egr valve never closing. Best check is to unplug egr valve electrical connector, removed egr tube that crosses the valve cover(since it the easiest to remove). Start the engine and there should be hardly anything coming out egr venturi outlet, you can hold your hand over the outlet with no resistance. We will attach a nitrile work glove on the outlet, with the engine running if it blows up and pops withing seconds you've got a bad egr valve. The egr gas will keep the exh. from reaching proper exh.
  17. Check for trash in the bajo fitting on the eecu cooler plate. I think the top fitting is the inlet. If noting there check at the filter base inlet for trash. I've seen small bits of trash float around inside the inlet under that plastic cap and block off the tiny fuel passage.
  18. If you have fuel jn the oil it could be a leaking o-ring or through the injector plunger and or body. To determine which, remove supply and return line fittings, plug one and apply no more than 20 psi air to the fuel galley. Use soapy water to find leak.
  19. How old are the injectors? Could be a cup leakage issue or the injectors could be the problem. When it is running poor? Is there air in the fuel return? You can see it in the return port in the fuel tank, if there are bubbles coming out in the return port you have leaking cups.
  20. There are cup plugs on the engine brake valve as well, make sure they are not loose or missing. Make sure the cup plugs on the rocker shaft are not missing or loose. Also, make sure all rocker shaft bolts are tight. It could also be an issue with the CCV spinner. There is a brass nozzle that sprays oil at the CCV spinner and could be loose or missing. Verify low oil psi with a mechanical gauge. Seen this issue several times on mp8 engines and response from e-service after checking everything was to replace the oil filter housing and that may be where you are headed. Attached is a PDF fo
  21. Possibly the ground relay on the firewall. When trying to start, the relay pops open and you loose voltage to the eecu because either the relay is going bad/bad connection or the starter is drawing too much amperage/internal issue. Use a jumper cable to jump the ground relay terminals and see if it starts. If it does start you need to check the starter. Remove the ground cables, measure resistance from the starter ground pole to a ground point on the block. You should have an open circuit, if you have resistance the starter is shorted out internally.
  22. Fuel transfer pump can leak fuel into the oil, there is an fuel galley plug under the front cover that can leak fuel into the oil as well. Usually there is fuel weeping around the fuel galley plugs on the front cover if the plug(s) are leaking. Best thing to do is remove the oil pan, use the fuel hand primer pump to charge the fuel system and try to find where its coming from.
  23. Check for fuel wicking around the plastic cap before the fuel primer pump. If you use the primer pump and fuel leaks around the cap you need to replace the cap--Mack has a replacement kit for it. If it is ok, remove the fuel tank caps, using a flash light check for air bubbling out the fuel return pipe in either or both tanks. If you are getting a consistent amount of air bubbles coming out the return fuel tube it is either leaking injector cup(s) or a faulty 7th inejctor "T"fitting check valve. Remove the air line to the 7th inj. "T" fitting, if it was faulty the air bubbles will eventu
  24. Make sure you have good air psi to the valve. Check and remove the eecu connectors to see if there is oil contamination. If there is the engine harness needs to be replaced along with the oil psi sensor and oil level sensor. A temp fix is to clean out the oil with electrical contact cleaner but the oil will wick right back----if oil contamination is an issue. Also, check the valve electrical contacts to make sure they are ok.
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