Misfire. 7 months still not fixed.

Need a bit of help with this. Had help from various members but sadly I'm not further forward.

Car runs fine until warm. Then start missing.

It's always come and gone but now it's here to stay and won't go away. An ecu reset used to solve the problem. But I found a few times it didn't do anything. So really it's just a random intermittent fault that I thought I was curing.

It starts to miss and then idles rough.

So far I've changed;

Coil + capacitor

Plugs

Leads

Dizzy

Dizzy cap

I had a mechanic who fitted my r154 check it over while it was there. He said he couldn't here cylinder 4 injector clicking.

So changed injector 4 and still misfire.

Needless to say I collected my car and said I'd fix it myself.

He said when he pulls the lead from cylinder 4 slightly the car runs sweet again when rough idle.

I'm loosing heart with this fast. I've been off the road since January fixing problems and still after spending a fortune on r154 bits and solving issues I'm still here.

Could it be the EMU is going wrong when warm. It's sat in the transmission tunnel so it isn't cold and does warm.

It could be the emanage, run it without it and see.

If your running bigger injectors put the stock ones back in just do you can test it

How do I run without the emanage. I tried running it without and it wouldn't even turn over.

I do however have 440cc in.

How do I run without the emanage. I tried running it without and it wouldn't even turn over.

 

I do however have 440cc in.

It should run on them but I would put the stock ones back in, did you fit the emanage with a harness or is it hard wired

It's hard wired in. So I'd need to spice all the wires back in.

When it's running cold it's fine. And it first comes back either when everything's been running a whole OR I go for a drive and as soon as it's into hard boost it misfires.

Any other easy way to check if it's ecu? Perhaps get another on loan and swap the fuel and ignition map?

You need to eliminate the aftermarket parts and the emanage is a big possibility

Just put some link wires in to put it back to stock and unplug the unit.

Won't take long and then you know

You could try another unit but I would take it out to be sure

You using the right impedance injectors?

It's hard wired in. So I'd need to spice all the wires back in.

 

When it's running cold it's fine. And it first comes back either when everything's been running a whole OR I go for a drive and as soon as it's into hard boost it misfires.

 

Any other easy way to check if it's ecu? Perhaps get another on loan and swap the fuel and ignition map?

Yea standard 7mgte ones. Got them off Ryan and bought the recommended resistors to go with back when I had it mapped first.

Thanks for your advice. I'll see what I can do.

Is the EMU actually mapped? the EMU is not great at injector latency and can cause similar symptoms, if you know how have a play with the settings, it wont do any harm and may cure it.

There is a resistor pack that needs adding for the TT injectors, I remember that. Certainly fixed a poor idle on mine. But before going down the parts-ferkling road, we can perform some useful diagnostics. The EMU can datalog a massive amount of information, so why not hook it up to a laptop and record the cold start all the way to it warming up and misfiring. You might find you've got too much duty going to the injectors causing it to run rich, that'd give it a dodgy idle and misfire. You could pull the map off as well and post it up here, if you've gone from 330cc to 440cc, both Ricky and I should be able to tell if the map is roughly right for that size change.

Can't see how pulling injector#4 would ever make the engine run sweeter

Scope patterns for the coils and the injectors, when it's fine, and when it's missing should tell you all you need to know. Find a garage with decent diagnostic facilities near you.

Use your hair-dryer set on 'cold' to cool the EMU and see if that answers your question?

I love the difference in tech level between those two answers

If someone thought I owned a hair dryer I'd feel sexually slighted!

I thought it more likely Noz had a hair-drier than an Oscilloscope.

If someone thought I owned a hair dryer I'd feel sexually slighted!

Male pattern baldness can be a real pain.....

Gorrit gooin yit?

Ordered coolant temp sensor. Thought I'd try all the easy jobs first. Limited on time lately so this is first try. Worth swapping the O2 sensor? Surely that's a closed loop system. Maybe worth comparing my wideband values to the ecu readout with the ecu software on the laptop sizzle.

Hopefully have it fitted when it arrives this week. After that I'll try and scope the injector outputs. Past that it'll be removing ecu.

Then I'll remove the injectors and resistors.

"He said when he pulls the lead from cylinder 4 slightly the car runs sweet again when rough idle."

That statement if true makes me think that there is a problem with the plug,lead,coil, or the EMU is messing with the signal.

The fact that it starts cold and then starts to miss eliminates the cold start side of thing's.

Noz, double check your wiring for the resistors. Make sure you've got the right black/orange wire for the injector cabling as I understand if you use the wrong one it can cause issues.

Check the wiring. It seems fine dude. It was an intermittent problem, so never led me to believe it was wired incorrectly.

I've removed the 440's and resistors. Now back on stock 330's. Same problem.

I've tried jumping the loom to get the stock ECU to work without the EMU and it idles so rough it's unreal. I've checked this method, and done it three times now. And exactly the same happens each time.

So I'm struggling to remove the EMU from the equation. Any advice before I start looking at trailers lol

If its had you beat for this long mate id take it to a good mechanic. Get it sorted whilst there is some summer months left to enjoy it.

Just on the off chance I had I miss on mine today thought it was tge coil/plug pulled up with it missing and pulled the coil clips off on each to see what cylinder it was on 6 , so swapped the coils over and plugs with 5 tested still missing looked at the injector/ wiring to injector and the actual coil clip prongs like the coil clip prongs where wide apart and give a bad conection intermitantly

You mayhave the same issue or well worth a try

Checked all recommendations.

AND now tried another emanage with no better luck.

Trying a new stock ecu next week.

Going to start looking at the wiring on the injectors.

Crazy annoying now.

Done a compression test. Nothing below 145 psi. Most are around 200 psi.

Misfire now present when engine isn't warm.

Considering trying to fully remove emu.

Going map will the stock ecu return to using the map?

what cams have you got fitted.