Fresh 1.9L Build , engine shuddering , rev hunting , won't hold steady RPM
 

Hello,

I have finally fired up my fresh 1.9L build!

Managed to get it half running in the rubbish basemap provided to me from the builder of the ECU (Extra EFI UK)

Then I had a remote tune booked last Friday.....I know it's not ideal in comparison to getting it RR tuned but he was going to make me a safe map with conservative timing and fuel just so I could drive about and run the engine in no boost etc
AN hour into the remote tune he requested if I could hold the RPMs at 2k while he adjusts parts of the map and I then found I couldn't....

When trying to hold 2K the car shudders and drops 200rpm then goes away
2000rpm , 1800 , 2000, 1800 and so on...

Everytime it "shudders" AFR goes to 17-18 also
From a bone cold start for the first 30-45 seconds I can hold the revs and it holds them perfectly
Ive leak down tested the engine and had 5% leak down on all cylinders
I have had the car running and shot brake cleaner at the injector seals to see if the revs increased (no change in RPM)
​​​​​I just want to upload the map/a few logs on here just to see if you can see anything that I've missed

When looking at the logs on MLV I can't see anything ECU wise other than AFR that is changing when the car shudders/runs lean I just want to be able to rule out an ECU setting or something interfering before I rip everything apart
Hope you guys can help
Spec
MK1 1.8 Block
​​​​​​Stock crank
Maspeeding Conrods
Supertech pistons
Wiseco Rings
ACL Bearings
ARP mains
ARP Headstuds
Boundary Pump
OEM Headgasket

BP4W Head (new seals, guides , skimmed , pressure tested
Stock cams
​​​​​​stiffer valve springs
Squaretop UK inlet
MK2 throttle body and IACV
Stock rail
Bosch EV14 640cc injectors
Coolant reroute
GfB developments Toyota COP kit
kraken manifold
GT2860RS
Kraken 3" downpipe
Kraken 3" system
Mtech cooler kit
Extra EFI PNPAEM 30-4900 Failsafe WidebandGM IATAEM 3port MAC valve

The lean spike is probably a misfire (not actually lean). Probably an injector or spark issue that is only happening when it gets hot?

What are your plugs and what’s the gap?

Thanks for the fast replies!

Luckily I have lots of spare parts (I have another working parts car that used to be my daily)

I removed the COPs setup and went back to OEM coil and leads and problem still persists
Swapped out the injectors for some standard maroon ones

Still happening
I've ordered all 3 tyres of injector seal (top hat to rail , injector to top hat , and the bottom cushions for the inlet)

Maybe it's sucking in air into the injector and not spraying?

BKR7E haven't touched the gap at all

Where's the tune and logs?

Haven't uploaded them yet , will fire up the laptop once I'm back from work

Did you gap them before install? Your supposed to gap them before install. I had a slight miss when I first got my turbo going because I gapped one of my plugs incorrectly

I haven't touched them
What's the recommended gap for the plugs?

I can’t remember. Google that shit brother

Will do , thank you for your help 🤘🤘

Gap should be .030.

Have you tried to turn EGO completely off?

I will upload the map/logs later

I will try all of the suggestions and get back to you all
I will also upload a video if I can of what it's doing cold Vs warm
Thanks everyone 🤘🤘

​​​​​​

Here are the unfinished tune and log attached

you can see at beginning of log when cold its holds revs and afr doesnt spike
once warm it starts acting up

i tried turning EGO off and made no change

i gapped plugs down to .030 still no change

here is a video of it running to give you idea


Many thanks in advance

I cant view the logs, but are you running closed loop or open loop idle? How about your idle VE settings. It sounds like a tune issues bc when it's warming up it has warm up enrichment that can be making it run decent, but once that ends it's based off your idle settings. I would run open loop idle for now just to get it running ok and then change to closed loop once you can tune more.

At the moment I'm running closed loop , I haven't set up the IACV setting for the MK2 valve on my MK1 basemap
I wanted to rule out any issues with that so currently the valve is switched off

At the moment I'm running closed loop , I haven't set up the IACV setting for the MK2 valve on my MK1 basemap

I wanted to rule out any issues with that so currently the valve is switched off

Select your entire fuel table and multiply by 1.15, see if that helps. If it’s running ok when cold, the extra fuel from warm up enrichments may be all you need. 1.15 will give you 15% everywhere. It’ll run rich where it’s currently ok, but it’s enough fuel where if I’m right, it should run better.

Have tried richening up the entire map and problem still persists

i have attached another log

Here is an sound check of what the running issue sounds like