Sorry this is going to be long. I have a Nissan Skyline 2001 model with a V6 engine vq25dd, milleage is 90000km. When i bought the car it had a rattling timing chain and plans were underway to have the problem rectified. Problems started when my usual mechanic travelled and i opted for another mechanic as the car was due for service. Little did i know that this guy was not well versed with that type of engine though he claimed he was an expert. I was there when he did the job - changing engine oil, oil filter, air filter, spark plugs and atf. This was the 3rd service after i bought it. All along the car was fine, good power, good start, good gear change, only the rattling sound was annoying and the was a CEL on.
Ok, so when the dude was done with the work i tried to start the car but it was only cranking, engine would'nt start. After several attempts it started but was misfiring, you could see the car vibrating. Initially he put the blame on the timing chain but i pointed out that i wasn't convinced - that problem was always there and there is nothing much that he had touched. Next he thought the plugs were defective and put back the old ones. I knew i had to see an experienced mechanic before this dude fried my engine. I drove off (obviously ). The car started smoking on the right front side, strong smell of something like rubber or wires burning and it filled the interior. I stopped, opened the hood and obviously something had been burnt. I started the car again (hard start) and drove home, called another mechanic - real mechanic. I'll not go into the details of how i dealt with the first cowboy.

The symptoms on the car were -
1. rattling sound (chronic problem),
2. hard starting,
3. CEL light (chronic problem),
4. misfiring,
5. where did the smoke come from?
6. jerking when accelerating

The car was plugged to the OBD11 and it picked codes relating to timing chain and the mass air flow sensor. Then the mechanic also discovered that the connections to the plugs on one side had been wrongly connected. He rectified that and the misfiring immediately stopped. The hard starting persisted though. He advised me to look for iridium plugs as i had been using NGK plugs all along which are not recommended by Nissan. He also rectified the rattling chain problem, the tensioner was nolonger working properly. Now the engine is quiet when running. He then told me to look for a new MAF sensor. The car is still hard starting, sometimes i give up cranking the engine.

>>I don't know if this MAF sensor defectiveness is progressive because now it stalls with the sensor plugged in but if you unplug it the engine, once running, will be smooth though you can't got above 1.5 revs because it jerks.

>>Is it only the MAF sensor or there are other wires etc that need to be replaced. The mechanic assured me that once the sensor is in place all the problems will go away but im worried about the smoke i saw.

>>what could have happened and what's the way forward?

What codes do you have now?
Are you saying the car still smokes?
If yes, at what point does it smoke? While driving or when you start it?

Yes, as Nissparts asked, what are the current codes? Try a new MAF sensor as suggested by the mechanic. You said Nissan did not recommend NGK plugs for the car. All well, do you have the manual on the specifications? Well, I'm just curious here because the early Infiniti G35, which is a cousin to the Skyline, uses the platinum-tipped plugs not iridium.

No, it only smoked once. After i restarted it that day and drove home it nolonger smoked. The only problem right now is hard starting and MAF sensor problem. If i plug it in it stalls, if i remove it the engine is as quiet as a church mouse, so smooth, just that I can't rev it. Im yet to plug it to the OBD11 again, quiet expensive this side. I can put it in any gear without any hesitation eg when washing it.

Change the MAF then since you had that code before but it would be great to be sure by scanning it now.

I'm with you Costee. NGK plugs are cheaper this side, about $7 per plug while the BOSCH plugs are at least $35 per plug and i'll need 6. I remember being told they are iridium plugs but what I'm sure about is there are top quality plugs that need to go in there, not the usual NGK double head plugs. Will try to get the codes this week if i fail to get them tomorrow. My worry is that i hope MAF sensor is the only problem that needs to be sorted out.

Early Nissan ECU's allow you to read any stored fault codes without any specialist equipment.

Below will show how you can read yours. The orientation of the plug may vary so please make sure you are looking at the plug the right way up before you try this on your car.

First of all you need to obtain the consult diagnostic plug location. This us usually in the same area as the fuse box under dashboard.





Once you have located the consult plug you then need to grab yourself a short piece of wire or a paper clip.

Please read all the following instructions in full before you attempt to carry a fault code read out.

Switch the ignition to the ON position but do not start the car.
Depending on its orientation of the consult plug (see below) bridge the two lower left, or upper right pins on the consult plug with the wire paper clip for 2 seconds then remove the bridge.

Observe and write down the sequence of flashed produced by the engine check light on the dash. using the information provided above.
Once you are satisfied you have all the fault codes bridge the consult pins again and this will erase any stored fault codes and revert the ECU back its normal operation.

Understanding the fault code readout:

ECU fault codes are usually displayed on the engine check light on the dash, and are displayed by the number of flashes as well as the speed of the flashes.

For example, an ECU showing no recorded faults will display code 55. The first digit is shown as 5 followed by a pause. This then followed by the second digit. This is shown as 5 short flashes. Thus Code 55 - all clear.

Listed below are the fault codes for the skyline

11 - Crank Angle Sensor/Camshaft Position Sensor
12 - Air Flow Meter
13 - Engine Coolant Temperature Sensor
14 - Vehicle Speed Sensor
21 - Ignition Signal
22 - Fuel Pump
23 - Idle Switch
24 - Throttle Valve Switch
25 - Idle Speed Control Valve
26 - Boost Pressure Sensor
27 -
28 - Cooling Fan Circuit
29 -
30 -
31 - ECM
32 - EGR Function
33 - Heated Oxygen Sensor
34 - Knock Sensor
35 - Exhaust Gas Temperature Sensor
36 - EGR Control-Back Pressure Transducer
37 - Knock Sensor
38 - Right hand bank Closed Loop (B2)
41 - Intake Air Temperature Sensor
42 - Fuel Temperature Sensor
43 - Throttle Position Sensor
45 - Injector Leak
47 - Crankshaft Position Sensor
51 - Injector Circuit
53 - Oxygen Sensor
54 - A/T Control
55 - No Malfunction
63 - No. 6 Cylinder Misfire
64 - No. 5 Cylinder Misfire
65 - No. 4 Cylinder Misfire
66 - No. 3 Cylinder Misfire
67 - No. 2 Cylinder Misfire
68 - No. 1 Cylinder Misfire
71 - Random Misfire
72 - TWC Function right hand bank
76 - Fuel Injection System Function right hand bank
77 - Rear Heated Oxygen Sensor Circuit
82 - Crankshaft Position Sensor
84 - Automatic Transmission Diagnostic Communication Line
87 - Canister Control Solenoid Valve Circuit
91 - Front Heated Oxygen Sensor Heater Circuit right hand bank
94 - TCC Solenoid Valve
95 - Crank Position Cog
98 - Engine Coolant Temperature Sensor
101 - Front Heated Oxygen Sensor Heater Circuit right hand bank
103 - Park/Neutral Position Switch Circuit
105 - EGR and EGR Canister Control Solenoid Valve Circuit
108 - Canister Purge Control Valve Circuit
111 - Inhibitor Switch
112 - Automatic Transmission Speed Sensor
113 - Automatic Transmission 1st Signal
114 - Automatic Transmission 2nd Signal
115 - Automatic Transmission 3rd Signal
116 - Automatic Transmission 4th Signal
118 - Automatic Transmission Shift Solenoid Valve A
121 - Automatic Transmission Shift Solenoid Valve B
123 - Automatic Transmission Overrun Clutch Solenoid Valve
124 - Automatic Transmission TOR Conv Solenoid Valve
125 - Automatic Transmission Line Pressure Solenoid
126 - Automatic Transmission Throttle Position Sensor
127 - Automatic Transmission Engine Speed Signal
128 - Automatic Transmission Fluid Temperature Sensor

jabbatings: I'm with you Costee. NGK plugs are cheaper this side, about $7 per plug while the BOSCH plugs are at least $35 per plug and i'll need 6. I remember being told they are iridium plugs but what I'm sure about is there are top quality plugs that need to go in there, not the usual NGK double head plugs. Will try to get the codes this week if i fail to get them tomorrow. My worry is that i hope MAF sensor is the only problem that needs to be sorted out.

NGk has iridium too! But it seems Nissan prefers platinum. I guess that is really unimportant now, as the issue of the plugs has been solved. We face the MAF

Iridiums are actually recommended for the skyline

nissparts: Iridiums are actually recommended for the skyline

That's settled then.

You got me there Costee
Just had a look at the connector, it's a bit tricky. Seems to have 2 more holes, unless others are redundant. Maybe will try that tomorrow after work, just had a few beers.

For good measure, you should find any of these MAF part numbers applicable for your car:
22680-6N200
22680-6N201
22680-6N20A
22680-6N211
22680-6N21A

While changing the MAF Sensor try and change the Temp Sensor as well. Temp Sensors are sometimes the main culprits of vehicles hard starting and rough idling. According to the factory Service manual of my jeep the engine coolant temperature sensor is something that, when bad, can cause a rough idle, misfire, and general poor running of the engine..

Goodluck and let's have your feedback..

Hi guys. Sorry for the silence im still waiting for the MAF sensor. It's being shipped from Japan, will get it soon then will update you. It's quite expensive

jabbatings: Hi guys. Sorry for the silence im still waiting for the MAF sensor. It's being shipped from Japan, will get it soon then will update you. It's quite expensive

Japan! Where are you at? What part number are you expecting?

Hi. I'm in Zimbabwe. I decided to wait giving the go-ahead to get the part from abroad. I called in an auto-electrician. He decided to use MAF sensor of the same type from another car that was working. Still the same symptoms were manifested - engine hard starts, idles without sensor but if you plug it in it stalls. He will try my MAF sensor on that other car tomorrow. Could it be that the original MAF sensor is working? He says there may be problems in the fuel delivery system, the MAF sensor may simply be reporting to the ECU that there is an imbalance somewhere. He says the fuel pressure and plugs need to be checked. Earlier my mechanic had noted that the fuel was dirty. Does the computer scan tool pick up every problem on a car or it just gives you somewhere to start from? What baffles me is the main problem started all-of-sudden. The auto said he has to cross- check the connections made in case there was a misconnection somewhere.

One more thing i'll be getting new recommended plugs in 2 days times. You won't believe someone is selling them at $35 per plug, managed to source them from a genuine dealer at $10 per plug. That's how it is that's why i want to avoid going through unnecessary expenses.

jabbatings: I called in an auto-electrician. He decided to use MAF sensor of the same type from another car that was working. Still the same symptoms were manifested - engine hard starts, idles without sensor but if you plug it in it stalls. He will try my MAF sensor on that other car tomorrow. Could it be that the original MAF sensor is working? He says there may be problems in the fuel delivery system, the MAF sensor may simply be reporting to the ECU that there is an imbalance somewhere. He says the fuel pressure and plugs need to be checked. Earlier my mechanic had noted that the fuel was dirty.The auto said he has to cross- check the connections made in case there was a misconnection somewhere.

Yes, all these are possibilities. keep us posted. I asked the part number of the MAF. What's it?

I don't want to lie. I looked at the sensor removed from my car there is no mark, even my mechanic couldn't tell. The other sensor from the other car looks identical and it fits with the connections. Is there a way to tell which is which and what are the differences from the list you gave me.

jabbatings: I don't want to lie. I looked at the sensor removed from my car there is no mark, even my mechanic couldn't tell. The other sensor from the other car looks identical and it fits with the connections. Is there a way to tell which is which and what are the differences from the list you gave me.

The part# is indicated on the housing containing the sensor and not on the sensor itself. I want to believe that the sensor you swapped from the other car was compatible since it's same model. But then, how did you know what sensor you requested from Japan?

The dealer requested for the car details and came up with the number which corresponded with the one you gave me (coz afterwards i asked for the part number he wanted to order just to make sure)

jabbatings: The dealer requested for the car details and came up with the number which corresponded with the one you gave me (coz afterwards i asked for the part number he wanted to order just to make sure)

Ok then. Fingers crossed.
NB:Tell the dealer to unplug the battery for about fifteen minutes before the installation of the MAF

Noted will update you

You were right, it's written 226806N200 on the housing

Today im celebrating. The GT250 roared back to life and I hit 180 on a test drive . So this is what happened. Yes, the original MAF sensor was defective and the mechanic I worked with had reassured me that once 1 replaced it i'll be home and dry. I did exactly that like I noted before and still the problem persisted. The symptoms persisted - hard starting, engine cutting once the new MAF sensor was plugged in, rough idle, poor revs. I had this gut instinct that something small had gone wrong and decided to seek help from an autoelectician. Besides I started doubting the expertise of the mechanic 'cause he was saying a vq25dd uses short reach spark plugs when in fact I knew they were long reach plugs (thanks to internet). I knew i had to seek second opinion.

The first auto assessed the car and concluded that there was fuel starvation, he thought the high pressure fuel pump was failing that's why the engine was cutting off. A new pump was bought and installed. Still the problem persisted. I could see this guy had no other tangible differential diagnosis and dropped him at once.

Then I saw a second auto, this guy is good. I don't know what he did but he told me the connections hadn't been in contact behind the engine so the ECU was not receiving the proper signals, something to do with the memory getting jumbled up. The job didn't take long at all. I later learnt most 'good' autos were actually taught by him.

Lessons learnt:
-please don't let anyone touch your car unless you're sure about the expertise
-keep your car tuned to factory standards, use recommended products
-insist on a definitive diagnosis first before parting with money
-not everyone knows everything, don't hesitate to seek second opinion
-patience and persistence pays

Thanks guys for your input.

All's well that ends well. Glad your car has been restored to living ways again. Safe drive.

hello friends I have a Nissan Altima 2002 that's stalling during drive. I live in niger state and its hard to get a sound mechanic/ parts. code on obdII shows IAT sensor and incorrect gear ratio. how can I get an IAT sensor for my Altima

emejiro: hello friends I have a Nissan Altima 2002 that's stalling during drive. I live in niger state and its hard to get a sound mechanic/ parts. code on obdII shows IAT sensor and incorrect gear ratio. how can I get an IAT sensor for my Altima

Post here:
https://www.nairaland.com/1317206/official-nissan-infiniti-thread
Post the error codes too. You'll probably need to change your MAF sensor.