Poor idle after switching to XIM with 2.05

chasmat2316

Well-Known Member
Joined
Nov 7, 2006
I can't seem to get the car to idle as clean as it did before I installed the XIM. What tables should I be looking at that have effect on XIM cnp should I be looking at? I see a dwell table what should it be set to?
 
You can start by tuning the dwell override off and see if that's the issue. What coils are you using?
 
Noise from plug wires can be a factor. The Dwell tables included the latest release (Not what is preset in the XFI) are a good baseline. Instead of running 5 ms dwell all the time it will run a ramp based on TPS. I doubt this will be your issue since you would most likely just be reducing the coil dwell anyway at idle.
AG.
 
We are assuming he has good data in the dwell override tables. My reason for turning them off was to verify this wasn't the problem and eliminate that variable. Some of the early 2.05 downloads had a bad dwell.ict
Since the kit was purchased from Hartline Performance, you are also welcome to contact us directly if that makes things easier
 
We are assuming he has good data in the dwell override tables. My reason for turning them off was to verify this wasn't the problem and eliminate that variable. Some of the early 2.05 downloads had a bad dwell.ict
Since the kit was purchased from Hartline Performance, you are also welcome to contact us directly if that makes things easier

The only assumption I was making is that he was running without dwell override and the default tables are not correct as many people would overlook loading in the good ICT files. Without override than probably not a factor.
If you're assuming he's running with override than its possible it could make a difference. If no override than probably no improvement to be found with idle quality.
AG.
 
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If you turn of the dwell override, it doesn't matter what is in the dwell tables. Until 2.05 came out, everyone ran CNP this way. The cars would idle ok off those default tables. Depending on how "bad" the idle is, this would eliminate bad data in the dwell override tables. On the early 2.05 software, I would see issues loading the default dwell.ict tables.

The main thing I'd to help the OP. After lookibg at the dwell override The next thing I would look at, is the cam signal, crank signal, and crank error to make sure we're not dealing with a noise issue
 
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The dwell override feature was put in primarily to accommodate non-GM applications using dumb coils or GM LS type coils. However, it is a nice feature for anyone wanting and knowing how to program the dwell. Cal is correct that with current firmware, having the dwell override turned off will work as it always has with GM applications: 2.5mS dwell during cranking and 5mS dwell everywhere else. This works pretty good with 90% of LS type smart coils. If you don't want to bother with programming dwell parameters, turning off the dwell override feature is a safe choice.

Pre 2.0 calibrations will have uninitialized calibration memory where the dwell override parameters are stored and anyone migrating a calibration from pre 2.0 to 2.0 will need to check this along with all the other new parameters added. There is an ICT file included that will program generic dwell parameters to make this easier.
 
Lance in version 2.01 dwell was preset at 2.5ms at idle and 5ms everywhere else?
 
If you turn of the dwell override, it doesn't matter what is in the dwell tables. Until 2.05 came out, everyone ran CNP this way. The cars would idle ok off those default tables. Depending on how "bad" the idle is, this would eliminate bad data in the dwell override tables. On the early 2.05 software, I would see issues loading the default dwell.ict tables.

The main thing I'd to help the OP. After lookibg at the dwell override The next thing I would look at, is the cam signal, crank signal, and crank error to make sure we're not dealing with a noise issue
thanks Cal, you did convert my file to work with 2.05 for me. the thing is the car ran great before the xim install? I'm wondering if a table is just set wrong somewhere?
 
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