Back again to ask you guys for a bit more help.

 

Got my Zed back today with a new mot but seems to have a bad stuttering issue when it reaches 2500rpm in all gears, the revs also hunt a bit too on idle and this seems to happen when both cold and up to temp.

Cars a manual UK TT.

 

Any advice would be appreciated

have u unplugged the maf ? if not try that see what the idle is like then.

 

ECU showing fault codes?

http://www.twinturbo.net/nissan/300zx/forums/technical/view/1105629/The-Ultimate-Guide-to-ECU-Diagnostics.html

The 2.5K limit could be ECU Fail Safe condition for MAF (see FSM EF+EC page attached). In the first instance have a look

at the MAF connections for corrosion/damage.

EF+EC 32.pdf

Edited September 29, 20205 yr by AndrewG

Thanks for the suggestions guys,

I wont be able to get back to the car until wednesday but will try unplugging the maf and see what's it runs like.

I'll also use the guide you've posted there and see if there are any codes pop up too, never had the time to do it tonight.

 

Would the maf go bad if the car had been sitting around for too long? Been in the garage getting work since the start of lockdown so around 6 months now.

MAfs go bad by just looking at them funny, I had one that passed all the voltage tests, so I passed it of as working fine. Tried everything else, still didnt fix the problem. Went back to the MAF, replaced it and the problem went away. Can you borrow one to test on the car?

I wish I did mate though I don't know anyone else in my area with a Zed to ask.

Maybe it was wishful thinking to hope that Zed MAFs weren't as bad as Vauxhall ones Haha.

I'll be heading down tomorrow after work to have a poke around and check the codes, would it help to try cleaning it first?

Much appreciated for the help guys, turned out to be the MAF! Took it off and gave both it and the cone filter a good old clean out, now she revs like normal ?

I am a bit worried about the MAF connector though because it's easily disconnected even with the spring clip in place, might be a good idea for a cheeky cable tie?

1 hour ago, Maduri said:

I am a bit worried about the MAF connector though because it's easily disconnected even with the spring clip in place, might be a good idea for a cheeky cable tie?

Is the spring clip correctly seated?

It is mate, double checked when I was at it yesterday.

Same happened to me today. On the way to work it didnt feel right. Felt like it was wearing a face mask past 3500rpm on the way to work. On the way home felt fine. Done about 5 miles and as i was slowing for roundabout lost all power and car died.  Would restart but dies straight away again. Found a vacuum hose off driver side throttle body. Put it back in. Now the car wont die. But idle wanders between 500-1500 rpm contantly but doesnt misfire. Doesnt rev above 2500 either. Tried to unplug maf. No joy. Let me know what you find as it seems a similar problem.

Sorry to hear about the problems you're having with your Z mate.

As it turned out the main issue with mine was the MAF that needed a damn good clean after being sat in an mot garage for months thanks to covid, the sporadic work being done to it and the constant start stop was sucking up all sorts of grime into the MAF so all I did was take it off and give it a good clean out with electrical contact spray from halfords  replugged and she seems to be in good order now, couple of days back and forward to work with no issues.

Could maybe try giving the MAF a clean out? Or like the other guys here said try checking if you have codes on the ecu since shes put herself into limp mode?

Same thing, swapped the mafs just now. Purrs like a kitten again. Shame that a simple thing like this can leave you stranded roadside.

Aye it is pretty daft that something so small can cause such a big headache but I guess that's cars nowadays eh?

Glad that you found the source of the problem though!