Running rich / cutting out issue **RESULT!**

Decided to start a new thread as the other one is really confusing, so for those who don't know my car suddenly cut out and wouldn't start again for half hour.

When it did eventually start the revs were really low and it would cut out when coming to a stop. Showing check engine light and both oil can lights.

when Starting the car from cold it no longer idles at 2000rpm but 1000rpm dropping to 3/400rpm, after 2/3mins the revs jump around and struggle to hold the revs, at which the car sounds awful and sounds like its knocking? It then cuts out with the engine check light on and both oil cans?

With just the ignition on I get both oil can lights and engine check light on which don't go out unless I start the car.

Diagnostic check - no codes (used to work perfectly but now sometimes doesn't even flash) unless I give it a whack.

Tps - tested ok

Map sensor - tested ok

Water temp sensor - hard to test since I can't get it up to temp but I managed to got these figures:

02.1 cold

1.3/1.2 2mins running

00.5 after a huge 6mins of running

Things Iv borrowed or replaced

Greddy map sensor

Engine ecu

Idle control valve

Fuel pump ecu

Ignition coil

Spark plugs I replaced 2weeks before for NGK Iridium BKR7EIX 2667 so decided to put the old ones back in BKR7E 6097

The last thing I will be checking are

Compression

TT ffim leaks

And any wires Iv messed around with will be getting checked over.

Failing this I'm all out if ideas!!

Crankshaft & camshaft sensors? They should flag up with a code, but you never know...

Dont shoot me down in flames but you did not put the wrong fuel in on the last top up did you? Just chucking in some possible ideas

Seems a few NA-T's having issues at the moment, picked the wrong time to just buy one myself perhaps !

Crankshaft & camshaft sensors? They should flag up with a code, but you never know...

Well it's certainly something else I can add to the list. Thanks

Dont shoot me down in flames but you did not put the wrong fuel in on the last top up did you? Just chucking in some possible ideas

 

Seems a few NA-T's having issues at the moment, picked the wrong time to just buy one myself perhaps !

Lol I'm not ruling it out I do use a diesel van most days!

I wouldn't worry about being na-t I'm pretty sure this could have happened even if I was still NA?

Crankshaft & camshaft sensors? They should flag up with a code, but you never know...

After searching Iv learned the na doesn't have these sensors and reads its position from the distributor any ideas how to test?

Simplest way is to swap it with a known good one.

And make sure you put it back correctly or it will run like a bag of nails and need the timing reset.

Ahh, sorry matey. For some reason I thought you had a TT. I'd change the leads as well if they haven't been changed for donkeys. It seems quite common for NA's to be suffering from ignition issues these days due to old HT leads.

Given that you have a TT/NA inlet manifold conversion did you make sure the ECU grounds on manifold are tight?

Lyndon

Simplest way is to swap it with a known good one.

Thanks will look into getting a spare to try.

And make sure you put it back correctly or it will run like a bag of nails and need the timing reset.

It couldn't possibly run any worse

Ahh, sorry matey. For some reason I thought you had a TT. I'd change the leads as well if they haven't been changed for donkeys. It seems quite common for NA's to be suffering from ignition issues these days due to old HT leads.

Lol no worries mate I only spent most of last night searching.. Iv no idea when the ht leads were changed but they look in very good condition.

Given that you have a TT/NA inlet manifold conversion did you make sure the ECU grounds on manifold are tight?

 

Lyndon

They are tight lyndon but I'm going to remove the manifold to check a few wires Iv messed around with in the loom so I will check them again!

Thanks everyone especially lyndon and chris Wilson who have been very patient walking me through things to try!

Continuity checks passed on the wires I previously messed with, I'd like to inspect the injectors while the manifold is off, is there anything I can do myself other than check the seals?

Also I remembered something today while searching the net for answers, what would cause too much fuel pressure? Basically when I would fuel up releasing the fuel cap the pressure would be so great it would hiss the entire time, and I could feel the pressure behind the cap forcing it into my hand?? Nothing like it used to be like?

Well still no result although I did a compression test today and I'm no expert but I guess these are good for a 19yr old car?

#1 - 190

#2 - 200

#3 - 200

#4 - 212

#5 - 200

#6 - 200

Now I think I need to focus on the injectors, and harnesses they are 550's from the rx7 cleaned and flow tested I will do a continuity check from the ecu to the loom connecter on both wires, is there anything else to do?

Also the engine light is bugging me now when it cuts out I try to pull any codes but it won't flash! Just stays lit up?

When I restart it sounds like a bag of nails and instantly cuts out!

that's some seriously high umbers there

Is this a bad thing? Never done it before so here's the procedure I followed.

Since I can't warm the engine up it was done from cold

All plugs out

#1 efi fuse pulled

Held throttle open while I cranked for 5 times

Did you take off the inlet manifold at any point, I had a similar (ish) issue not so long ago and it turned out that I had put the manifold gaskets on the wrong way round, not sure if this is your issue, but hope you work it out, I feel your pain trying to get the damn thing to work!!

It's been off but long before this issue started, I'm exhausted trying to figure it out! Also just tried another tps just because I had one spare but I can't even get it to start now! And it still won't let me pull any codes?

I even though about buying toquicktostop aerotop and swapping the turbo and manual box but when I suggested it to the misses she quickly shot me down with the locks will be getting changed if I do...

:help:

I think my O2 sensor is goosed? But let's start at the mysterious fumes/smoke coming out when I remove the spark plugs..

I attempted 2 starts just now but as usual it would fire then quit on me instantly! So pulled the plugs and the light smoke came out of no1 / 2 / 4 cylinders? Is this just fuel fumes?

Anyway cranked it over to clear the bores, fired her up but held the throttle open @2k, then after 2mins i let off and it held the rpm @3/400rpm so quickly got a reading from pin ox1 for the O2 sensor and it read a steady 0.3v am I right in thinking its bust?

Were the plugs wet when you pulled them out?

They wasn't dripping but 2 or 3 of them were a little wet..

They wasn't dripping but 2 or 3 of them were a little wet..

If they where wet then they didnt burn the fuel, that would show lean afr though being there would be loads of unburnt air, have you checked ht leads and dizzy

Im not convinced the o2 sensor would be causing overfuelling to the point of flooding the engine, but if its not within the tolerances, I would change it anyway as a rule of thumb. Definitely check over the ignition system and gap the spark plugs if they're still looking in reasonable order. How do they look, btw?

Im sure the o2 would not do that 100% as I run mine with the o2 unplugged for a couple of months,

Im pritty sure that the explaination in the first post " revs at 400rpm and sounds like its knocking" is actually the engine running on 5/4 cylinders, so this could be

1, HT leads not in correct order

2, bad HT leads

3, bad dizzy

What if anything did you touch before this started happening?

Well guys tuck your advise to check for spark by removing efi #1 fuse removed no1 spark plug and put

It back into the ignition lead and cranked it over, now weather this is the right procedure I don't know but it fired up rather too well? So unplugged the tps too but it still fired up rather too easy.. Anyway carried on checking the rest of the plugs and they all had spark! So decided to start her up with both the efi#1 fuse and tps unplugged... Result!! Started up idled for 2mins @2k dropping to 1100 and it's still running as I type this! Afr's showing 10.9 slowly climbing but it has always taken a while to settle at 14.7 normally when Iv drove it for 1/2miles.

Think il try it now with the efi fuse back in but leaving the tps unplugged and see what happens?

I think you have a lead braking down dude and because you are moving them testing the plugs your making the good connection, or pulling the fuse has reset all your fuel trims

Guys you have no idea how relieved I am! It's running!!!

I know what the cause is now but don't know why it's failed? Or why it's decided to work all of a sudden?

Basically lyndon aka Nodalmighty sent me a spare ecu to try but when I fitted it it seemed to hunt more than before so I switched off thinking this wasn't the issue but left it fitted while I tried a few other things then today after checking for spark and finally getting it running with the efi fuse removed and tps unplugged I let it warm up then plugged them back in.

Since I needed to return lyndons ecu I swapped it out and what do you know it started ruff and the engine check light was on!

Swapped it back and all is fine again, I'm rather confused why its decided to work now only after today's fiddling???

Would like to thank everyone who has suggested things to try especially lyndon and chris Wilson who have walked me through testing procedures!

Original thread for anyone with similar issues:

http://www.mkivsupra.net/vbb/showthread.php?311465-Think-Iv-killed-my-na-t-cuts-out-after-5mins-idle/page2