acey

Hey all. I have been trying to diagnose a issue I am having with my car. Pulls strong up to almost 6000rpm, after that there is a weird hesitation where it feels like the car hits a brick wall and then power comes back. Sometimes even happens a few times before reaching red line. This is 100% repeatable and is more noticeable in the higher gears. I have had zero luck trying to solve this issue with the fuel table. I believe this is a ignition issue since this hesitation occurs once the boost creeps up to 9-10psi. I'd love to have a more calibrated eye take a look at my logs before I start spending money.

Some details on the car:
1.6L with full MK Turbo kit
currently the car is on wastegate. but creeps to 10ish psi by redline
stock ign coil
NGK Blue Plug Wires
NGK BKR7E gapped to .024"
DIY MS3

Thanks!

whiprsnapr

I’d start with a set of coils. I forget what the upper limit on the stock ignition is. I’m not good at looking at ms files, so maybe someone can chime in. I’m on Toyota cop’s and I get blowout gapped above .028. 14lbs.

If if it’s not ignition, boost cut is the only place my mind would go.

nicholaschase29

Sounds about right. I had the issue on my 1.6 around that PSI with stock coils and upgraded for flowforce's D585 coils. Blowout was an abrupt drop in power for an instant.

Can you adjust the wastegate so that it boosts to 8psi and see if the issue goes away? Or just take your foot out of it and try to hit a lower psi and see if it goes away.

As an experiment you could gap the plugs even closer and see if it goes away....

In any case, you're going to want to upgrade the stock coils.

sixshooter

iTrader: (12)

Where is your boost cut set?

Schroedinger

Just as a data point- I’m running 1.6L with BK7RE’s gapped to 0.024” and stock coils. Strong up to 14psi. Agree to check overboost settings in MS.

acey

Boost cut is set to 12psi. I’m not able to turn down the boost any more, my internal wastegate is not flowing efficiently enough so the boost creeps up in the higher rpm. Logs show the car makes like 10.5psi so I pretty confident it’s not that boost cut.

I’ll experiment around with partial throttle, and re gapping plugs. Seems like there is plenty of people running around my boost level with stock coils not having issues. Eventually plan on a COP setup. But I’d like to pinpoint the exact issue before doing that. I can upload my tune if anybody wants to take a look.

x_25

The boost cut on the MS3s is a bit weird. If it thinks you are going to hit it, it will cut. Try raising it two psi and see if that helps.

That said, my friends car does the same thing, even with good plugs gapped down. I think his coils are just tired. He is running on a Link ECU, so it's not boost cut on his.

My 1.6 pull strong at 10.5psi no problem, but I had to bump boost cut up to 14psi cause I would occationally have it kick in at 12psi.

WigglingWaffles

I think the MS3 anticipates your boost creep will go higher (take it to the limit) and cuts early. Try bumping your overboost protection up a little. I have stock ignition and run 12 psi to redline with no problemo.

sixshooter

iTrader: (12)

Predictive boost cut

Schroedinger

..and if you’re walking it back to root causes, port your wastegate better.

acey

For sure less noticeable when doing a partial throttle pull up to redline.

I will try upping overboost protection.

Thanks for the input.

18psi

iTrader: (76)

spark blowout

nicholaschase29

Curious if you worked this out and what it was.

acey

still haven't fixed this... installing LS coils in the next couple weeks. I will update if that fixes the issue

acey

figured I should update this. Installed LS Coils from Flow Force a few weeks ago. Problem solved.