Retarded timing...

98lincmk7lsc

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This is on my black 98.

I've noticed for a while that I'm losing power in the top end. It's still pretty quick, but I can tell it's not putting out what it should be.

I hooked up the Xcal2 with the SCT live link datalogging software, and from what I can tell, it's retarding timing when I get on it.

Rather than tell you guys what I've tried, and taint your replies, I'm gonna ask for your recommendations, and I'll say whether or not I've tried it (or even thought about it). lol.

What could be causing it? Feel free to ask for any clarifying information.

Thanks!

BTW, I only use 93 octane gas.
 
I believe that generally, with most cars, WOT will bring back the timing to prevent pre-detonation at higher RPM's, and this is not including how much more the knock sensors are pulling back on..
 
From looking at the modifications you have listed in your signature... The first question I have is about your CIA... Where are you drawing air, inside or outside the engine bay? I'm not a fan of metal CIA's since they tend to heat soak during hot summer time.

I ask this because combustion temperatures do affect performance. Which leads me to spark plugs. I'd suggest pulling and analyzing each cylinder looking for signs of pre-ignition and/or high speed glazing. If this is the case you'll need to drop a heat range or two on your plugs.
 
What are the IAT and ECT readings?

-Alan

I'll have to check. I haven't done much datalogging at all.

I believe that generally, with most cars, WOT will bring back the timing to prevent pre-detonation at higher RPM's, and this is not including how much more the knock sensors are pulling back on..

I've heard this, however it seems to be pulling much more than it should be. On my stock 97, the car seems to accelerate more and more as the RPM's climb, but the 98 seems to stagnate, if that makes sense...

It feels much like what I imagine a car with stuck-closed IMRC's would feel like. However, I've had the intake off and cleaned the IMRC's and verified that they operate perfectly and that they opened up when they should once I reinstalled them.
 
From looking at the modifications you have listed in your signature... The first question I have is about your CIA... Where are you drawing air, inside or outside the engine bay? I'm not a fan of metal CIA's since they tend to heat soak during hot summer time.

I ask this because combustion temperatures do affect performance. Which leads me to spark plugs. I'd suggest pulling and analyzing each cylinder looking for signs of pre-ignition and/or high speed glazing. If this is the case you'll need to drop a heat range or two on your plugs.

This is what I've got...
http://www.lincolnvscadillac.com/showthread.php?t=69465

I never got the chance to make a new one with a lid yet, so that's what I'm using for now.

Also, I should note that it's not due to the hot weather we've been having. It's been acting like this for a while, and the winter weather didn't affect it any differently.

I do plan on checking the spark plugs if I get a chance this weekend. I might just replace them anyway.
 
It could be either the PCM is retarding timing due to high IAT and/ECT temps, torque management not turned off in between shifts or you are getting Knock Retard and it's pulling timing because of that, or a combination of all some or all of those things. Need to datalog.
 
Since you can datalog, you should look at the following things: engine rpm, IAT, ECT, timing, long term fuel trims, knock retard (KR). Do a couple WOT runs and report back.
 
got a wideband?


try adding a touch of fuel up top. with your mods it could be going lean enough to piss off the knock sensors. or toss in a couple gallons of race gas to see how it reacts.


also datalog and report results
 
Since you can datalog, you should look at the following things: engine rpm, IAT, ECT, timing, long term fuel trims, knock retard (KR). Do a couple WOT runs and report back.

I'll see what I can do about that tomorrow. I'll post up what I get.

got a wideband?


try adding a touch of fuel up top. with your mods it could be going lean enough to piss off the knock sensors. or toss in a couple gallons of race gas to see how it reacts.


also datalog and report results

Yes I do. Unfortunately, it's not hooked up yet. :(

I need to get a sensor boss welded in and then route the wires. It's a PLX Devices SM-AFR, with a digital multi-gauge display to go with it.
 
Nevermind my comments about the mods. I thought i saw cams in there for some reason
 

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