Cold start's / bigger cam.. please help..
#1
Cold start's / bigger cam.. please help..
Posted this in another area.. Cold someone please elaborate..?
I have a Comp Cam 232 / 236 .595 .601 114+4 cam with True duals, Yank SY3500, full bolt on's and it was tuned with HP Tuners...
When i start the car in the morning ( on cold days ) the car fires right up but it bucks, sputters, searches for idle... once warmed up ** approx. 5-10 min.. it is running fine....
It jumps from 200rpm to 4000rpm's... & up & down...
Someone mentioned the "Cold start enrichment"...
Any help would be greatly appreciated... Could this damage my recently built motor?
Thanks in advance..
I have a Comp Cam 232 / 236 .595 .601 114+4 cam with True duals, Yank SY3500, full bolt on's and it was tuned with HP Tuners...
When i start the car in the morning ( on cold days ) the car fires right up but it bucks, sputters, searches for idle... once warmed up ** approx. 5-10 min.. it is running fine....
It jumps from 200rpm to 4000rpm's... & up & down...
Someone mentioned the "Cold start enrichment"...
Any help would be greatly appreciated... Could this damage my recently built motor?
Thanks in advance..
#2
I had the same problem but with my stock cam, and my dual cutouts were open. It happened last year in about 25°F or below. This year, with my GT2-3, it did the same thing, but cutouts closed. I wasn't driving but my it stalled on my brother after we backed out of the driveway. In the first situation, what I had to do was hold the throttle down to keep it at about 2000 RPMs for a minute or two before it stopped screwing around. I too would like to know why this happens.
-somebody
-somebody
#3
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You could try a couple of things. Modify the open loop VE and add fuel for the colder temperature ranges and/or increase the timing in the converter light off table which pulls a **** load of timing (~12*) so that the engine doesn't hunt. You could also modify the idle tables to run 1000-1200 or higher until slightly warmed up. Once it begins hunting the PCM will continue to overcompensate (fuel and spark) under and over causing an erratic behavior.
#4
TECH Senior Member
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Originally Posted by technical
You could try a couple of things. Modify the open loop VE and add fuel for the colder temperature ranges...
Start-up enrichment will help if it is sputtering and stinky for the 1st 30 seconds or so. Your problem is 5 - 10 minutes so the enrichment table is not the primary factor.