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val245
06-09-11, 10:07 PM
Cunt of a thing, Astron EFI turbo engine, haltec ps1000 ecu, running a xf coon throttle body. Its got a xf IAC valve hooked up, one hose before throttle plate, on throttle body, and the other hose off the IAC onto the plenum just behind throttle plate.

Had one guy who wired up the ECU (qualified auto elec) set it up also, wasn't too bad starting, then the guy who tuned the car fucked around with it and make it worse.

Now I know that some of the problem is to do with the fuel system and it not having fuel pressure straight up to start engine, but once I prime it a few times (5 or so) you can crank it, and crank the engine till it slowly kicks, and kicks and kicks. By this time the valve is pulsing like crazy, the engine runs like a dog and at around 500rpm... barely, then it idles up, and down and kinda sorts itself out.

Now how the fuck do I get this to run correctly? I'm not near the car at present but will have to connect the laptop to see how its been set up... ideas?

Opinions on running a Camry or Tarago cold start injector to help?
Glenno
06-09-11, 10:17 PM
Fix the tune simple as that. Most aftermarket ecu's can manage idle using ignition timing pretty well without the IAC valve.
val245
06-09-11, 10:22 PM
The tune is fine, all I want is to walk up, hit the key and it to idle up untill warm then come down to the desired idle. once warm it starts fine. The mixture has already been enriched to help but it needs to work for cold starts. I understand ignition timing being used to help cold starting, but I want to try and make the IAC work before i chuck it.
Glenno
06-09-11, 10:38 PM
By fix the tune I meant the cold start/idle section. You won't need a cold start injector. Do you have a check valve on the fuel pump?
val245
06-09-11, 10:40 PM
It's a VLT bosch 077 fuel pump, they have the check valve internaly? I will grab a fuel pressure gauge and check it.
val245
08-09-11, 10:33 AM
?
gmh265
08-09-11, 10:38 AM
Had one guy who wired up the ECU (qualified auto elec) set it up also, wasn't too bad starting, then the guy who tuned the car fucked around with it and make it worse.



You said it yourself really, it sounds like the cold start is not setup correctly.
val245
08-09-11, 10:42 AM
You said it yourself really, it sounds like the cold start is not setup correctly.

obviously but Id really like to hear from other peoples experiences on setting them up/ or people running a xf throttle body with a different cold start setup.
gmh265
08-09-11, 11:44 AM
obviously but Id really like to hear from other peoples experiences on setting them up/ or people running a xf throttle body with a different cold start setup.

I don't think the type of throttle body really matters.. better off speaking to someone who knows the ecu you are using..
HoonBoy
08-09-11, 01:18 PM
I've used a Falcon throttle body on an Astron, cold start wasn't a problem and we spent bugger all time on it as it was a race car and didn't matter. I didn't use an IAC. Go back to the tuner and sort out the tune on it.
val245
08-09-11, 01:48 PM
did you have any sort of stepper motor? I will be doing returning it to someone with a better idea.
HoonBoy
08-09-11, 02:03 PM
None. Idle up wasn't a concern for me. It idled a bit rough for a minute or two but it was fine after that.
10sec rx7
08-09-11, 02:15 PM
The tune is fine,

clearly it is not,

the PS1000 has some of the best cold starting options avaliable on any after market ecu,

have you checked the fuel pump is running when cranking?