My car is a 91 with a 305 and a throttle body and I'm wondering why it cranks for much longer than normal when I start, but only from cold starts. If its already warm then it starts right up. What's the problem? Or is it just an older car thing?

 

sounds like it might be your temp sensor. The one on the intake, not the one in the driver's side head.


How much longer crank time are you talking? Here is a resistance chart at different temperatures. Use a multimeter and check the resistance cold.


https://www.thirdgen.org/forums/atta...ase-ctsmat.gif

 

I've been battling this issue forever on my TPI. Replaced all ignition and fuel components with no change. Will test the temp sensors...

 

Have you done a leak down test to check for pressure leaks?

 

Yep. Everything is 100% perfect. All parts are brand new end to end, and everything tests within spec. Zero vacuum leaks, etc. Even have a new MAF.

Not meaning to detract from OPs post. His is a TBI so could be totally unrelated.

 

Check your values with a scanner with cold engine. I also had cold start issues last spring, turned out my 5V circuit in the ECU was the problem. It gave less than 5 Volts, so for example the temp sensor reported +30 degrees C, when it was +6 degrees. Also the TPS reported 20% throttle at WOT. Replaced the ECU, and it was good again.

 

Check your fuel pump relay, may be waiting for oil pressure to build up before the fuel pump kicks on.

 

its weird has done it since i bought it. The other thing is that sometimes when it is warm it starts up and revs up to about 1200-1300 then drops down and dies, unless i quickly put it in gear before it dies.

 

Same exact isue in my tpi as well, only from cold start. Let me know what u find

 

ECU and CTS are on my list currently. Will advise as soon as I have the car back (2-3 weeks). She's in in the paint shop!