NA6 lack of power up hill

oozmakappa · Postby **oozmakappa** » Sat Apr 04, 2015 10:59 pm

Hey guys just wanted to ask around if anyone's experienced this issue i've been having recently

everytime i rev the engine, there seems to be a slight hesitation as the engine revs past 2000RPM, but after that short hesitation it goes all the way up to 5000RPM without any issues, it definitely isn't an AFM issue as i've recently replaced it with a working one. power is present at high RPMs but at low RPMs it's terrible.

Just the other day i was trying to go uphill in it (perhaps a 30 degree incline) and there was absolutely no power on the car even on 1st gear, i was literally crawling uphill and had to pull over to the side to allow the cars behind to pass.

has anyone experienced an issue like this, or if so any possible culprits??

project.r.racing · Postby **project.r.racing** » Sun Apr 05, 2015 8:52 am

ignition. probably leads or coils are failing. or where they connect together is failing.

93_Clubman · Postby **93_Clubman** » Sun Apr 05, 2015 10:37 am

Did you identify what the following was & why it was occurring?

oozmakappa wrote:...there were several drops of black oil on the floor, it has the consistency of water mixed with black stuff... ...anyone got any idea what it could be? A theory i have is that it's coolant...

viewtopic.php?f=29&t=67680

bruce · Postby **bruce** » Sun Apr 05, 2015 11:17 am

Spark plug leads.

oozmakappa · Postby **oozmakappa** » Sun Apr 05, 2015 12:15 pm

93_Clubman wrote:Did you identify what the following was & why it was occurring?
oozmakappa wrote:...there were several drops of black oil on the floor, it has the consistency of water mixed with black stuff... ...anyone got any idea what it could be? A theory i have is that it's coolant...

viewtopic.php?f=29&t=67680

hey clubman!

nope, haven't been able to, like mentioned before i only could tell where leaks were coming from after long drives, and seeing as this lack of power issue keeps coming up... i can pretty much forget about finding the source of that leak till my lack of power issue is solved :cry:

bruce wrote:Spark plug leads.

project.r.racing wrote:ignition. probably leads or coils are failing. or where they connect together is failing.

alright guys, i'll try to replace the spark plug leads, but do you guys know any way to troubleshoot the coil pack on how to tell if it's still functioning?

oozmakappa · Postby **oozmakappa** » Sun Apr 05, 2015 1:16 pm

oozmakappa wrote:
93_Clubman wrote:Did you identify what the following was & why it was occurring?
oozmakappa wrote:...there were several drops of black oil on the floor, it has the consistency of water mixed with black stuff... ...anyone got any idea what it could be? A theory i have is that it's coolant...

viewtopic.php?f=29&t=67680

hey clubman!

nope, haven't been able to, like mentioned before i only could tell where leaks were coming from after long drives, and seeing as this lack of power issue keeps coming up... i can pretty much forget about finding the source of that leak till my lack of power issue is solved

bruce wrote:Spark plug leads.

project.r.racing wrote:ignition. probably leads or coils are failing. or where they connect together is failing.

alright guys, i'll try to replace the spark plug leads, but do you guys know any way to troubleshoot the coil pack on how to tell if it's still functioning?

updated! i took out my spark plug leads and did a resistance test, they average out at about 1.4 ohms, and i reckon that's the average across all of them, so would it be the coil packs issue then?

93_Clubman · Postby **93_Clubman** » Sun Apr 05, 2015 5:00 pm

oozmakappa wrote:do you guys know any way to troubleshoot the coil pack on how to tell if it's still functioning?

If you know someone with an NA6 swap in their known good one, otherwise you can check inside the turret/post tops of the coilpacks where the sparkplug leads plug into as sometimes contact can be poor - the silver metal should be visible about half way down inside turret/post tops. Alternatively, as the coilpack contains two coils, with each coil running two cylinders, you can swap them around, but this tends to be of use when you've got a miss or non-firing in a cylinder or cylinders, & by swapping you make the miss or non-firing move to the other cylinder or cylinders.

oozmakappa wrote:took out my spark plug leads and did a resistance test, they average out at about 1.4 ohms, so would it be the coil packs issue then?

Checking sparkplug leads for use in NA & NB MX5s in this way is not reliable. Many have appeared to test ok, only to find when they ruled everything else out & finally replaced sparkplug leads the problem went away. Again, ideally if you know someone with an NA or NB8A swap in their known good leads to troubleshoot, otherwise buy a set. That said, given manga_blues following post, it's sounding like coilpack:

manga_blue wrote:Mine failed progressively over a few months. It was most noticeable on a long climb on a warm day. The car would just lose more power the further up the hill you went, presumably as the coilpacks overheated. For a long time there was no missing or anything obvious like that. It felt more like the brakes were dragging.
I didn't nail the problem until finally the ignition cut completely on 2 cylinders and when I pulled over you could smell the heat in the coilpacks.

http://www.mx5cartalk.com/forum/viewtop ... 5&start=15

Magpie · Postby **Magpie** » Sun Apr 05, 2015 5:02 pm

A localised Gravity Anomaly is causing your NA6 to weigh more and the lack of power of a NA6 is amplified.

http://www.ga.gov.au/ausgeonews/ausgeonews200809/gravity.jsp

project.r.racing · Postby **project.r.racing** » Sun Apr 05, 2015 9:09 pm

testing for resistance is not the way to test them. it wont find cracks or pinholes in the leads.

start engine. idle. pull out one lead at time and lay parallel to head cover about 1cm away. if the spark comes out anywhere other than the end, you have problem.

and do other end of leads near coil also. except this time looking of reduce spark.

Wuey · Postby **Wuey** » Sun Apr 05, 2015 10:28 pm

Before swapping parts, I would visually check for the obvious first. Since you have a NA6, your engine could have a short nose crank. The common problem for lack of power while going uphill is worn crank nose keyway. Visually check whether the main crank pulley wobbles.

When my previous NA6 started to have problem with the spark plug wires, the car had no problem going uphill but it would miss or hesitate while accelerating at speed.

oozmakappa · Postby **oozmakappa** » Mon Apr 06, 2015 3:15 pm

hey guys i tried all your suggestions today and did a check on the spark plug leads, there was sparking at the elbow bends when i laid the leads parallel to the cam cover, however the coil packs seem to be fine so far, i just ordered some leads from supercheap, anyone got a spare used coilpack i could borrow? i've also read about people using toyota COPs which seem to be a lot more reliable than the NA coil packs, can anyone verify this?

thanks for all the help guys!

Magpie wrote:A localised Gravity Anomaly is causing your NA6 to weigh more and the lack of power of a NA6 is amplified.

http://www.ga.gov.au/ausgeonews/ausgeonews200809/gravity.jsp

brah if you don't have anything useful to contribute please don't troll

Magpie · Postby **Magpie** » Mon Apr 06, 2015 3:37 pm

Toyota COPs are reliable, however if you do not have an aftermarket ECU you will need a circuit to adjust the dwell timing. Unless you have a heavily modified engine the money could be better spent elsewhere. Have a read here http://www.miataturbo.net/useful-saved-posts-8/upgrading-coil-plugs-all-years-cop-writeup-12704/

Can I go back under my bridge now that I have contributed something almost useful?

project.r.racing · Postby **project.r.racing** » Mon Apr 06, 2015 6:10 pm

seems you have holes in your lead. just replace them first, and if problem persist, then start looking elsewhere.

93_Clubman · Postby **93_Clubman** » Tue Apr 07, 2015 11:11 am

oozmakappa wrote:i've also read about people using toyota COPs which seem to be a lot more reliable than the NA coil packs, can anyone verify this?

NA6 coils are fairly reliable - not as reliable as NA8 coils, but much more reliable than NB8A coils. Also, a number that converted to Toyota CoP found they failed quite quickly as they were knock-offs or similar.

oozmakappa · Postby **oozmakappa** » Wed Apr 22, 2015 3:11 pm

UPDATE!!!

Alright guys, so i managed to get my hands on a set of coils from a friend, swapped it out and plugged it in (together with new leads of course) and the problems disappeared for a bit but came back again, although its slightly better than before.

Would it be a CAS problem in this case?