Jessyj Posted September 7, 2009 Share Posted September 7, 2009 I’ve posted a topic already about my pathy not reving past 2800 rpm, my plugs are black so I think the truck is running rich it’s not burning the fuel, the ecu keeps giving me a Maf senor code, but we’ve already test that with a new one but it runs the same, Know after some research I’ve come to notice that when I start the truck and let it run awhile my temp gauge stays limp( it lift just an inch or 2) so I’m guessing that my coolant temp sensor has gone bad. So here my question is it possible that it might be the problem? Oh btw a temp sensor here is like $36. And I really don’t want to spent more $ without that being the problem. This will be my last effort or else I’m taking to the mechanic Link to comment Share on other sites More sharing options...
Nismojunky Posted September 7, 2009 Share Posted September 7, 2009 try disconnecting the sensor and see if that helps Link to comment Share on other sites More sharing options...
Nismojunky Posted September 7, 2009 Share Posted September 7, 2009 and btw if it is the sensor i have a brnad new one from nissan here id let go for 20$ + shipping Link to comment Share on other sites More sharing options...
Jessyj Posted September 7, 2009 Author Share Posted September 7, 2009 try disconnecting the sensor and see if that helps I already did that it just gets worse Link to comment Share on other sites More sharing options...
Jessyj Posted September 7, 2009 Author Share Posted September 7, 2009 I already did that it just gets worse Where are all the guru's ? I can't believe that no one is albe to help me solve this problem Link to comment Share on other sites More sharing options...
Airrun2002 Posted September 7, 2009 Share Posted September 7, 2009 Try replacing the pcv valve? And runnig some fuel system cleaner through it? Also Try disconnecting the battery for 10 min to reset the computer after you replace the maf. could also be clogged fuel filter. simple cheap fixes hope it helps. Link to comment Share on other sites More sharing options...
beastpath Posted September 7, 2009 Share Posted September 7, 2009 Where are all the guru's ? I can't believe that no one is albe to help me solve this problem no offense, but a little patience wouldn't go amiss. people will help, but not everyone is online all the time. plus today is a holiday, I expect most people are doing things in the real world. as far as your problem... you should replace the temp sensor if it is bad, even if you take it to a mechanic they will replace it, so it is cheaper to do it yourself. IIRC when timing belts slip a tooth or so it can cause rpms to not rev over a certain limit. see if wiggling the wires to the maf sensor helps at all. sometimes the problem is a bad connection there. Link to comment Share on other sites More sharing options...
Jessyj Posted September 7, 2009 Author Share Posted September 7, 2009 Try replacing the pcv valve? And runnig some fuel system cleaner through it? Also Try disconnecting the battery for 10 min to reset the computer after you replace the maf. could also be clogged fuel filter. simple cheap fixes hope it helps. Thanks for the input, did do that will try later today thanks i'll keep you posted Link to comment Share on other sites More sharing options...
Kingman Posted September 8, 2009 Share Posted September 8, 2009 It's a possibility. If it gives you code 11 or 13 then it is your ECU coolant temp sensor. It's located in the valley of the engine and a shop will rate it at 6.5 hours labor at whatever they charge. That sensor went out on my old '87 and it was an $850 something repair bill. There are 2 coolant temp sensors on these trucks. I'm pretty sure that code 11 is for the gauge and code 13 is for the ECU to adjust how much fuel to dump in the engine. That sensor should read between .3-1.7 ohms. When my sensor went out it was giving the ECU 120 ohms! That effectively told it that it was -1564561564156454313245616321787651321532 degrees outside and to dump a half a tank of gas into the engine in 14 miles. Neither of those sensors have anything to do with each other, either. If your ECU is telling you that you have a bad MAF you may have a broken wire somewhere. Link to comment Share on other sites More sharing options...
Jessyj Posted September 8, 2009 Author Share Posted September 8, 2009 It's a possibility. If it gives you code 11 or 13 then it is your ECU coolant temp sensor. It's located in the valley of the engine and a shop will rate it at 6.5 hours labor at whatever they charge. That sensor went out on my old '87 and it was an $850 something repair bill. There are 2 coolant temp sensors on these trucks. I'm pretty sure that code 11 is for the gauge and code 13 is for the ECU to adjust how much fuel to dump in the engine. That sensor should read between .3-1.7 ohms. When my sensor went out it was giving the ECU 120 ohms! That effectively told it that it was -1564561564156454313245616321787651321532 degrees outside and to dump a half a tank of gas into the engine in 14 miles. Neither of those sensors have anything to do with each other, either. If your ECU is telling you that you have a bad MAF you may have a broken wire somewhere. Thanks for the info, i'm going to get the help of a friend this wknd and check those wire again. btw i change the coolant temp sensor but the guage inside is still not working Link to comment Share on other sites More sharing options...
Indigent Posted September 8, 2009 Share Posted September 8, 2009 (edited) It's a possibility. If it gives you code 11 or 13 then it is your ECU coolant temp sensor. It's located in the valley of the engine and a shop will rate it at 6.5 hours labor at whatever they charge. That sensor went out on my old '87 and it was an $850 something repair bill. There are 2 coolant temp sensors on these trucks. I'm pretty sure that code 11 is for the gauge and code 13 is for the ECU to adjust how much fuel to dump in the engine. That sensor should read between .3-1.7 ohms. When my sensor went out it was giving the ECU 120 ohms! That effectively told it that it was -1564561564156454313245616321787651321532 degrees outside and to dump a half a tank of gas into the engine in 14 miles. Neither of those sensors have anything to do with each other, either. If your ECU is telling you that you have a bad MAF you may have a broken wire somewhere. On the VG30E motors, the coolant temp sensors are up in front of the engine just before the large black tube that goes to the radiator. The one that gives the ECU the temp signal is the onewith the yellow shell connector. The only thing in the trough between the heads is the knock sensor. Edited September 8, 2009 by Indigent Link to comment Share on other sites More sharing options...
Kingman Posted September 9, 2009 Share Posted September 9, 2009 I was unaware they moved them. Thanks for pointing that out so it doesn't get repeated! Link to comment Share on other sites More sharing options...
Jessyj Posted September 9, 2009 Author Share Posted September 9, 2009 I was unaware they moved them. Thanks for pointing that out so it doesn't get repeated! I installed a new coolant temp sensor but the guage still won't work, i really think i have some harness issues Link to comment Share on other sites More sharing options...
Terrano1992 Posted September 9, 2009 Share Posted September 9, 2009 I’ve posted a topic already about my pathy not reving past 2800 rpm, my plugs are black so I think the truck is running rich it’s not burning the fuel, the ecu keeps giving me a Maf senor code, but we’ve already test that with a new one but it runs the same Code 12 (Mass Air Flow Sensor circuit) means not only MAF sensor itself, but MAF sensor wiring faults also. You have already test your MAFS (by replacement with a new one without any changes). So, you have a wiring (harness) failure... Probably, your temp gauge harness has faulty also... Main rule of diagnostics: don't replace "faulty" sensor before you examine sensor harness. Link to comment Share on other sites More sharing options...
Jessyj Posted September 9, 2009 Author Share Posted September 9, 2009 Code 12 (Mass Air Flow Sensor circuit) means not only MAF sensor itself, but MAF sensor wiring faults also. You have already test your MAFS (by replacement with a new one without any changes). So, you have a wiring (harness) failure...Probably, your temp gauge harness has faulty also... Main rule of diagnostics: don't replace "faulty" sensor before you examine sensor harness. I'll keep that in mind for next time,i'm going to tackel that harness this wknd, gone keep you posted Link to comment Share on other sites More sharing options...
GrimGreg Posted September 9, 2009 Share Posted September 9, 2009 You should have 2 different temp sensors, one for the ECU and one for the guage. Link to comment Share on other sites More sharing options...
Jessyj Posted September 9, 2009 Author Share Posted September 9, 2009 You should have 2 different temp sensors, one for the ECU and one for the guage. Where is the one for the ecu located? Link to comment Share on other sites More sharing options...
k9sar Posted September 9, 2009 Share Posted September 9, 2009 I thought they were side by side Link to comment Share on other sites More sharing options...
WiredWrong Posted September 10, 2009 Share Posted September 10, 2009 I’ve posted a topic already about my pathy not reving past 2800 rpm, my plugs are black so I think the truck is running rich it’s not burning the fuel, the ecu keeps giving me a Maf senor code, but we’ve already test that with a new one but it runs the same, Know after some research I’ve come to notice that when I start the truck and let it run awhile my temp gauge stays limp( it lift just an inch or 2) so I’m guessing that my coolant temp sensor has gone bad. So here my question is it possible that it might be the problem? Oh btw a temp sensor here is like $36. And I really don’t want to spent more $ without that being the problem. This will be my last effort or else I’m taking to the mechanic Can you tell me if all your cylinders are firing ? whats your timing like ? did you hit the distributor ? Link to comment Share on other sites More sharing options...
Terrano1992 Posted September 10, 2009 Share Posted September 10, 2009 I'm pretty sure that code 11 is for the gauge and code 13 is for the ECU to adjust how much fuel to dump in the engine. Oh, no. Code 11 means Camshaft Position Sensor failure (CMPS located inside the distributor). Code 13 is Engine Coolant Temp Sensor. You can test it with ohmmeter. ECTS nominal resistance is 2100-2900 Ohm when engine is cold (20C/68F) and 300-330 Ohm when engine is hot (80C/176F). You have two coolant temp sensors on VG30E. Sensor with 2-pin connector is used by ECU (code 13 when fault), and sensor with single pin - by dash temp gauge (no error codes, but gauge shows incorrect readings). Link to comment Share on other sites More sharing options...
Kingman Posted September 10, 2009 Share Posted September 10, 2009 Code 13 and 98 are the Coolant Temp Sensor codes. My bad. 13 is for the ECU. Link to comment Share on other sites More sharing options...
schickdog Posted September 17, 2009 Share Posted September 17, 2009 hey guys, little clarification please. 88 vg30 and trying to replace my sensor. I have replaced the temperature gauge sensor and that's all good. but, i don't see the coolant ECU temp sensor. there is a plug just to the left of the gauge sensor that is capped with an allen head bolt. I don't see the temp sensor anywhere. any help please? THanks! Link to comment Share on other sites More sharing options...
schickdog Posted September 18, 2009 Share Posted September 18, 2009 anyone? Link to comment Share on other sites More sharing options...
Kingman Posted September 20, 2009 Share Posted September 20, 2009 It's in the valley of the engine, below the intake. Link to comment Share on other sites More sharing options...
Jessyj Posted September 24, 2009 Author Share Posted September 24, 2009 Ok here is where i stand(i'm going nuts) the pathy is getting to much gasoline, some mechanic told to change the fuel pump, (but that didn't sound logical for me so i took it some where else) Now the new mechanic is telling me it's the ecu. i really need some advise on what to go here Link to comment Share on other sites More sharing options...
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