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Terrano1992

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Everything posted by Terrano1992

  1. I suggest to rotate MAF air duct (short metal tube with 4-bolt flange, bolted to air filter box), not a sensor itself (small black plastic box at the side of this tube). We are talking about MPFI (VG30E), of course. TBI (VG30i) design is totally different.
  2. MAF sensor can work in any position (upside down, for example). So, unscrew MAF from filter box, rotate it to a more suitable position (to release tension and sharp bend from a MAF harness) and screw back. Easy fix to a very common problem, yeah?
  3. Me think, total harness replacement is a more labor-intensive task than to unbind wire harness, locate short-circuit, wire breakage or other damaged points, repair them and rebind harness with new insulation tape... But it's only my opinion, make your own choice. Harness can look fine at a first glance, but total horror under the covering. Codes 12, 23, 34 and 51 are caused by bad harness/wiring in most cases. For example, if you have no power at MAF sensor (due to short-circuit or wire break), it will produce code 12 even with a good MAFS. Code 23 (idle switch, buried inside the throttle position sensor) - the same causes. Code 34 means wire break (or shorting) in knock sensor circuit. And code 51 means that injector circuit has too low resistance (injector driver overload, electronic overcurrent protection was activated each time when ECU tries to open a faulty injector). Code 45 (injector leak) follows code 51, when one or more injectors are open all time (because corresponding control wires has a current leak/short-circuit to the ground). Wiring problems again... So, your first step - visually check main ECU connector (under front passenger seat) for bad/bend/corroded contacts. Disconnect ground wire from the battery before remove/reattach connector to ECU module. Next step will require a multimeter (and basic skills to use it for electrical measurements). Measure voltage at corresponding connector pins to find, where is a damage. Locate damaged area and repair it. If you have no FSM, PM your e-mail address to me. I'll send EF&EC chapter to you in electronic form (Adobe PDF format). It describes all diagnostic procedures mentioned above step-by-step, with schematic diagrams and illustrations.
  4. Start from repairing fault harness under the hood, from engine to ECU. When all harness problems will be resolved, clear codes, run engine, test-drive and read codes again. All codes and repair procedures are well described into 1994 FSM, section EF&EC. 1994 Pathfinder ECU can't show Code 22 (fuel pump is not a self-diagnostic item on this model). Me think, this is your mistake with counting LED flashes.
  5. It sets code, but only if reading voltage from sensor is outside limits. I.e. 0 volt (shortened circuit) or more than 5 volt (short-circuit with another wire inside the harness). Intermittent faults of coolant sensor are not a rare case. They caused by wire crack inside the sensor. Crack breaks circuit at a certain temperature but reconnects when temperature is different, due to a thermal expansion of sensor body.
  6. Measure sensor resistance with ohmmeter first. It should be 2100-2900 Ohm at 68 deg.F, 680-1000 Ohm at 122F and 300-330 Ohm at 176F. Then check sensor harness, as described in 1994 FSM, pages EF&EC-86..87. Replace sensor when you're sure that the sensor wiring and connectors have no faults.
  7. Bad thermostat can be half-open when engine is cold and full-open when hot. In this case, engine will not overheat, but engine warming will be "lazy"...
  8. You are not right. ECU reads sensor as analog value and selects corresponding "fuel map" (i.e. amount of additional fuel) depending on coolant temperature. So, if sensor reading is way over "cold" (abnormally increased resistance of overall circuit, i.e. sensor and wire harness, due to a sensor/connectors/harness fault), incorrect fuel map (way too rich air/fuel ratio) will be selected, and exhaust backfire will be a result. Sensor replacement is easy task (on cold engine, of course). Unscrew old sensor, put a small amount of RTV silicone to a new sensor thread, screw in and moderately tighten.
  9. Powerful hairdryer switched to the max temp... "heat and detach"... But be careful, don't overheat tint film to a melting point (it is easier than you can think).
  10. Spray "Carb cleaner" or "Easy start" fluid to suspected areas when engine working at idle. RPM will rise when you spray to a leak point. Be careful - both fluids are EXTREMELY flammable! Don't spray too much and have a fire extinguisher at hand... Do you have backfire through the intake, or through the exhaust? In second case - probably you have faulty engine coolant temp sensor, not a vacuum leak.
  11. I suspect worn/leaky master brake cylinder first. And vacuum brake booster as second option. Check R-ABS also, if you have it.
  12. Yes. 1994 FSM, pages EM-12..EM-17 (timing belt removal and installation procedure). Tooth count is at bottom of page EM-15.
  13. You can select any brand, but Hitachi and Bosch are "Genuine Nissan" part manufacturers.
  14. 1994-95 FSM (Factory Service Manual) describes full procedure for "code 11" troubleshooting. Look at pages EF&EC-80..82. You can find this FSM in the internet (links was posted somewhere at this forum, try to search). Or, if you want - PM your e-mail address to me, I will send a copy of EC.pdf to you.
  15. Camshaft Position Sensor is integrated into a distributor. You can't buy it as a separate spare part... Make sure that your problem is exactly in a camshaft sensor (not in a sensor harness). Camshaft sensor malfunction occurs only in rare cases, most of "Code 11" problems related to faulty/damaged wiring and bad grounding circuits...
  16. I had similar issues with my tailgate overhead light, caused by corroded contacts inside connector and 3-position switch...
  17. 95 electronic speedometer powered directly from 12V. If it has internal voltage regilator, this thing buried somewhere on speedometer PCB. BTW, each gauge (temp, fuel) on 95 "round" dashboard has its own internal VR, not an external one. Me think, the last dashboard with external common VR was made before August 1992 (i.e. before 93 model year). The next step is vehicle speed sensor and harness...
  18. Terrano1992

    seafoam?

    ...and have a hydro-shocked engine to rebuild If you want try this - remove spark plugs again after soaking, crank engine 30-60 seconds, put plugs back. Now you can start engine. I figure this is a method to remove carbon deposits from piston rings...
  19. It depends on production date. Mechanical speedometers was used before October 1993, electrical after this date.
  20. AC belt tensioner or alternator bearings are most frequent sources of whine...
  21. If pressure rises to 37psi (it is nominal for Nissan TBI) but quickly falls after a pump stops, there are 3 plausible reasons. One-way valve (buried inside the pump) leak, injector leak or pressure regulator valve leak. Pinch fuel hose immediately after pump stops, to completely block fuel stream through this hose. If pressure stays high when you pinch the hose between fuel filter and TBI - probably you have a one-way valve leak. Stays when hose after regulator is pinched - regulator leak. Both hoses are pinched simultaneously, but pressure quickly falls - injector leak. Call a helper to switch ignition on/off/on again on your command, while you pinch hoses. However, if you have stable 37psi until fuel pump running, I don't think pump valve leak or regulator leak can cause any noticeable troubles with running engine. At the same time, injector leak can (air/fuel mixture ratio will be constantly rich).
  22. Check for left-side exhaust manifold leak...
  23. Insert your 1/2" socket into a plug opening and use a jack to support it (in other words, to firmly press socket into the plug and hold it). Then work with two hands.
  24. This is impact screwdriver, not a wrench...
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