Constant rpm popping and hunting

[Adrian Dawson]

Hello all. I'm having some issues with my sr 20 hopefully someone can point me in the rite direction. At idle or at any givin rpm it seams like it has an intermittent miss and idle/revs are not constant.seams to be alright when revving. the afr also jumps a lot between 12-16 at idle not as bad at higher rpm. When I adjust the master trim so it runs rich say around a 9-12 afr it seams to be not as bad. It's a new project and still trying to work out kinks before getting someone professional to tune it. Any help would be much appreciated. 

[Adrian Dawson]

 Also I cannot find any vacume leaks

[Scott]

Hi Adrian,

What is your ignition angle at the point this is happening?

Cheers,

Scott

[Scott]

Hi Adrian, 

Your ignition timing sounds like it is not changing much, so I don't think that will be the issue.

I do not have any data myself on the deadtimes for those injectors. A quick google search revealed this off a forum:

Nismo (16600-RR544) / Tomei (195017) / Apexi (404-N006) / HKS (1402-RN009)

aka JECS 740cc injectors (side feed, high impedance, circle, red)

voltage: msec
8v: 1.641
10v: 0.973
12v: 0.633
14v: 0.463
16v: 0.359
18v: 0.227

I do not know how accurate this information is, and so use it as your own risk.

Where abouts are you located and who are you thinking of getting to tune it? It could be worth contacting them for advice also. 

[Adamw]

Have you got any trigger errors showing?

[Adrian Dawson]

Yea those are the injector dead times I used as well. I will be getting dynolink in townsville to do it so ill wait till the rest of the car is done and take it to them. And no trigger errors showing. Thanks for the help guys much appreciated!