Thread: SR20VE Help Need-Ignition Timing Fighting Me - High RPM Misfire-Sounds Like Anti Lag

The problem I have is a misfire at high RPM.

I have set base idle to 25 degrees.

I use an AEM FIC to pull it back 10 degrees

However even with the FIC set to retard ignition by 10 degrees, timing light still shows 25 degrees advance at idle.

If I can change the retard at idle ie +/- 5 degrees with the FIC it will fix the problem for a day or so and then the misfire comes back.

First question, why do I see 25 degree advance when setting the base idle even though the FIC is retarding ignition by 10 degrees?

What ECU are you using? NA or boosted? Also why don't you set base @ 15 degrees then change your timing where you need it? I recently had my base timing set at 25 degrees on accident retarding 1 degree per PSI on pump gas and it liked to melt plugs

Hello!

NA for now.
ECU: AEM FIC with SR20DE ECU

The FIC cant advance ignition timing. So I advanced the timing manually hoping to pull the timing with the FIC.

No problems when distributor is clocked for 15 degree base idle.

I cant understand why base idle is showing 25 degrees when FIC is set to retard by 10.

ECU Talk shows 15 degree regardless of where I set the timing on the AEM FIC.

ECU Talk also shows high RPM wide open throttle at 25 degrees if I am having the misfire or not. It doesn't change.

If I didn't know better I would say the FIC is not doing anything but you can hear the engine note change when you change the timing settings at idle. Plus changing the timing settings at idle will fix the problem temporarily.

If I had to speculate I would say the Nissan ECU knows the timing signal is being manipulated and tuning back to what it thinks it should be.

I'll hookup a timing light on my RR car and retard the AEM timing table at idle and see if it changes at the balancer. I don't see why it wouldn't, I just haven't tried to tune it that way being boosted. What year is your ECU from?

From the sound of it the AEM may not be changing timing at all if your balancer mark doesn't move with timing changes from the AEM. And if you aren't running METH/Alcohol 10 degrees extra across the board is dangerous I learned that one a couple weeks ago

Thanks, let me know what you see

About the ECU Talk, would you expect the ECU Talk idle timing reading to match the timing light timing reading?

I have a consult cable but never used it. Before I tune a setup with the FIC I reset the ECU, Set base timing to 15 degrees, set the retard per PSI. Have setup 4 cars that way and never had a problem.

Also under setup / ignition are you set to MAP, MAF, or TPS ? We have always used MAP setting.

Yeah, MAP for ignition and fueling. Works a charm.

Yeah no issues at 15 degrees. But I want to advance timing to get the most from the VE.

I am starting to think the Nissan ECU has a failsafe built into that doesn't allow big increases in ignition timing by clocking the distributor. This is the biggest question mark for me at the moment.

Another reason to go turbo...

About turboing it, what RPM does the boost come in with a GTX3076R and what header and compression are you running?

edited

Get nismotronic before going turbo ..

Zeneffect. Okay so I have to add 10 degress to what the ECUTalk is giving. So when it says 25 degree top end it is actually giving 35 degree advance.

I am going to have to clock the distributor back to 15 and see what happens to the ECUTalk readings at the top end.

35 degree is plenty of advance but the sounds I hear (the problem) are like the timing is too retarded.