I swapped in a mild cam, 30 over bored 350 into my 91 Manual Trans Am (TPI) and for some reason it takes for ever to start. When I first started it for break in of the cam/lifters it started right up but now it take 10-20 seconds of cranking before it starts. New battery, injectors were cleaned and good to go, new fuel pump (granted its for a 305 if that is different), new fuel filter. Once it runs it runs fine, it jolts a lot while driving around semi consistently but thats another problem. It's just getting it started...

Any ideas? Thanks.

 

Are you saying your using 19#hr injectors and a stock 305 ecm calibration ?

 

No, new PROM Chip by Custom Chips for 350 Manual as well as a 350 knock sensor and then the 350 injectors.

 

Is the SES light coming on when it's running?

Probably a good place to start looking, assuming all sensors are doing what they are supposed to be doing.

I'd also check the fuel pressure. Not unusual for a new pump to be bad.

 

since your doing a custom prom , In closed loop your blm at idle looks good add fuel to cold start enrichment . The lower ve will effect starting , this should be a topic in the DIY prom section though.

 

It's not throwing any codes, I replaced the fuel pump about 2 years ago, drove many miles with it on the 305 so I'm thinking its not bad but I will check. Any sensors that I can check and how?

As for the chip, I didn't do it so I have no idea what any of that means???

 

Like Five7kid said using Tunerpro rt with a aldl to usb cable and the $8D adx file. Or a hand held scanner the older otc ones are fairly cheap on ebay. The Jurking if its on deceleration its a programing issue. If its while cruising I would think its from running lean or if this is a mild cam the iac function (Programing) and can be fixed if you datalog with whatever preferred program your tuner uses. I didn't realize there is a company called custom chips I was thinking you were doing a custom chip.Just to verify the block learn numbers at idle in closed loop, map values of 40-60 kpa, tps voltage .67-.76 iac count when warm 25-30 and that you have a higher iac count when cold start as well as a high idle. And just verify your base timing with your programmer done with the est disconnected. like five7 said this could be a bad fuel pump from sitting , depends on how long it has sat. So checking fuel pressure would be advisable and if low would solve the jurking or atleast help with it.

 

I actually got my chip from you, Tuned Performance. It jolts both on decel as well as just cruising constant speed. I have yet to send you a data log to adjust the tune so maybe that will solve my problems.
I will check the fuel pressure, I can't seem to find the email from you saying what to use to get a data log. What do I need again? Thanks

 

send me a email at brianlvs@yahoo.com and I will send you the correct data stream file.
The 1227730 ecm is a easy ecm to connect to. I think the cheapest cable is the 12 pin from aldlcables.com. You can use tunerpro rt for free.


http://tunerpro.net/
http://aldlcables.com/

 

I thought you were exerting to this company
https://www.facebook.com/pages/Custo...49489875293854


When you email me please include your full name and the cam specs,
I would of step a starter tune and saved it under your username or full name.