Nissan Repair Questions? Ask a Mechanic for Answers ASAP
Hi Jake ,
The lean codes did not come back .
No codes this morning .
The lean code did not come back .
The battery is in good shape and the engine cranks strongly .
Pressing the gas pedal does not help .
Thanks, ***** ***** check for spark for me?
I will check to see what happens to the spark when the engine is cranked later today - in about an hour from now .
Earlier today I checked to see if it is a case of fuel starvation . I have concluded that it is not short of fuel because after the initial priming ,I disconnected the fuel pump power connector and the engine still attempted to start about 4 times without the pump being powered - presumably operating on the residual fuel in the system . The only conclusion I can draw from this experiment is that the ECU is either preventing the sparks or the fuel injectors , or both due to some sensor problem .
well whether your missing spark or fuel can be a big difference in what's going on.
Generally a no spark condition is related to a cam sensor failure or a timing issue
where as no injector pulse is generally related to a NATS issue where the key registration is not being detected.
I checked the spark . When the engine briefly fires there obviously was a spark, but then if disappeared with continued cranking and would again appear at short intervals as the engine attempted to start .
I replaced the camshaft sensor with a known good unit without any
effect . I have purchased a crankshaft sensor and will fit it tomorrow .
Please le tme know if the crank sensor helps.
Tried to locate the crankshaft sensor from the top but could not find it .
Are you able to give advice on how to gain access to the sensor ?
Tried to locate the crankshaft sensor but could not locate it .
Any advice on how to access it ?
its on the back of the motor by the oil pan on the left side.
let me know if you need more assistance.
Ok thanks . I will jack the car up and have a look from underneath .
Hi Jake, I was able to gain access from under the car . The new sensor made no difference - in fact it only produced a very short burst of life every 5 tries , or so .
I replaced the old sensor and it seems to give a better response from the engine . The engine attempts to start every time and in fact would sometimes run on for about 3 seconds while the revs were going up and down . Is this possibly a clue ?
Thanks for the help so far ,
Hi Jake, I have checked the spark already - it seemed to stop when the engine stopped firing even though it was being cranked .
However, I will give the starting fluid a try .
Hi Jake , I tried the starter fluid , but it didn't help .
However, I noticed that the engine was firing for longer as kept cranking and then I pressed gas pedal down and it sprang into life .
After it ran for a while, I was able to stop and restart without problem .
I drove it for about 1 mile and seemed a little sluggish .
I then checked for codes and found
P0340 - Camshaft position sensor A Circuit Malfunction
P1612 - NATS Malfunction
On Tuesday I temporarily swapped the Camshaft sensor from an identical car and it made no difference and I put the original sensor
I am puzzled that the new Crankshaft sensor did not work as well as the original .
I have just gone out to car and it started second attempt . I cleared the codes and have driven a few miles . It is running well but sometimes hesitates a slightly under heavy acceleration .
No codes have returned .
If the cam chain has stretched and on starting from cold the tensioner has not properly tensioned the chain then the P0340 will be
Is this the kind of behaviour one would expect from a stretched
When I had the cam cover off, I could see 6 V-notches on the tensioner ram . Does this give a clue as to how far the tensioner has extended ?
The easiest way to know if the chain stretched would be to look at intake timing with a scan tool.
Before I went in to replace the chain I would at least scope the cam sensor or put a new one in first.
The tensioner should nto be fully extended though.
From your experience, can a stretched cam chain cause the symptoms that I am seeing ?
Stretched chains are pretty rare on these cars, they more often jump time then stretch.
Now the symptoms of a chain that jumped a couple teeth or a stretched chain include. hard starting, loss of power, hesitation or misfire.
Hi Jake, it certainly is difficult to start, but once going it is smooth and accelerates well .
I am still curious to know it the tensioner ram is at the end of its travel .
I was able to see 6 ''V' grooves on the ram where it comes out of its housing .
Temperature could be a factor . Today it started at the fourth attempt .
It was a warmer day .
Tomorrow I intend to change the oil and oil filter . Since the chain tensioner is oil pressure activated , it could have an effect .
Hi Jake, on various forums I keep seeing 10mm as being the maximum extension , though a local Nissan tech says he has seen them at 20mm .