Nissan Pulsar Euro 2003 QG18DE 1800 engine, manual

tmenz, Aug 8, 6:26am
Report from Daughter - haven't observed it first hand!
Intermittently 'shakes' and lacks urge and power.
Sounds to me like it's intermittently running on 3.
No engine check light or other indications so presumably ECU not 'seeing' a fault.
Haven't attempted any diagnosis as yet - thought I'd ask the 'general wisdom' first.
Q1 Are these prone to coil or plug cap problems!
Q2 Could it be an injector problem!
Q3 Is it safe to unplug the connectors from the coil packs for diagnosis or is this a no-no in terms of ECU damage!
jason18, Aug 8, 6:28am
QG motor very common for stretching timing chains causing these problems
kazbanz, Aug 8, 6:30am
The Pulsar "is" the bluebird silphy. I'd be checking for a faulty AFM and giving the whole injector area a clean out first.Yes they do drop out coil packs but more common is still the afm
jason18, Aug 8, 6:36am
Or was it the QR!
tmenz, Aug 8, 8:23pm
Thanks for that - is it common for the AFM to be intermittent!
tmenz, Aug 8, 8:27pm
It's only 80 000km so I wouldn't expect the chain to be failing yet - would chain problems be intermittent! The engine sounded quite OK with no nasty noises when I tried it!
kazbanz, Aug 8, 8:28pm
It gets worse and worse--IMO its one of the three things I suggested
kazbanz, Aug 8, 8:31pm
I can only speak from personal experience here not google etc.
The 1800cc engine in the pulsar/avenir/silphy/primera never gives problems unless abused by the owner--ie oil never changed etc.
The 2.0l engine of the same age does give the issues you describe--ie cam chain stretch. It is a different desighn not just a bigger version.
tmenz, Aug 8, 9:49pm
OK, I'll give the AFM a clean on spec and see if the problem goes away!
mm12345, Aug 8, 10:05pm
If it's like the AFM in earlier Nissans, then yes. Usually dry solder joints between the AFM socket and internal circuit board that will open circuit under vibration or when the engine is hot, but hard to replicate when checking with the bonnet up - as the signal voltages will measure fine, but it will crap out when you take it for a drive, but not trigger a fault code/check engine light.
tmenz, Aug 9, 2:38am
Thanks, good info - dry joints are something I'm familiar with.
tmenz, Aug 14, 10:52pm
This one has the electronics covered up with a lid that's rivetted on. Has anyone successfully dived into one of these to the extent of removing the rivets and using screws/bolts to reassemble! Any pitfalls on the way!
tmenz, Aug 19, 1:20am
OK, I have had it long enough to diagnose the problem.
It is an intermittent coil pack (#2). Fails when warm!
Supplementary question - where is the best place to obtain a replacement! Nissan! Wreckers!
I am assuming that Repco/Supercheap/Partmaster don't sell specialist items like this!
kazbanz, Aug 19, 1:51am
tmenz- Im not certain but I think you will find accessorry coil packs are available for them at ripco.
tmenz, Aug 19, 3:26am
Thanks Kaz, Repco had an aftermarket equivalent which fitted and works just fine. A bit expensive but expedient and easy, so daughter can have it back with some confidence!