Takes 3-5 sec to start car

[supkev]

So yesterday I had a brand new Magnaflow cat installed (weld in application), and after when I tried to start the car up it takes 3-5 long cranks compared to my regular start ups. The battery seems to be healthy what else should I check for. I have a fuel filter I need to replace and will do it soon, what could it be also.

[squidmaster]

Did they ground to the chassis before welding?

[imwhyteyo]

Check fuel pressure. Likely right about that filter.. o2 wouldn't really cause starting problems unless it was complete junk. Clean your icv too and head to ignition after that. Check for vaccum leaks as well. Clean inside the throttle body.

[ebox86]

...Check for vaccum leaks as well...

I concur with vacuum leaks as well, i had this happen on my 87, turned out the intake manifold gaskets were so old and cracked it was bad.

[jalopi]

IMO if it was a vacuum, O2 sensor, ICV, ignition or fuel problem it wouldn't run right while idling or going down the road - aka you'd have a performance issue too.

How old is the battery? How'd you deem it healthy?

[supkev]

IMO if it was a vacuum, O2 sensor, ICV, ignition or fuel problem it wouldn't run right while idling or going down the road - aka you'd have a performance issue too.

How old is the battery? How'd you deem it healthy?

yea i figure if it was a vaccum leak or any of the above my ca owuldnt idel or be able to accelerate normally. Battery is about 2 years old maybe Ill swap it out and give it a try!

[supkev]

I had a multi meter and checked my battery it's providing a constant 12v. My mechanic friend said also could be bad injectors or spark plug wires, cap & rotor.

[jlevie]

Intake leaks are the most likely cause. A smoke test is the way to find them. While there are other possibilities, rule out intake leaks by a smoke test first.

[jalopi]

What do you mean by constant 12V? Did you have someone crank the car over while you were looking at the meter readings? Because that would have to be one amazing, kickass battery to stay above 12V while cranking.

[ELVA164]

What do you mean by constant 12V? Did you have someone crank the car over while you were looking at the meter readings? Because that would have to be one amazing, kickass battery to stay above 12V while cranking.

Also, if you got 12V while the car was running it's no good. Running voltage should be in the 13.5-14.2V range.

[Jaxx_]

Also, if you got 12V while the car was running it's no good. Running voltage should be in the 13.5-14.2V range.

If this is the case, it's probably not a battery issue, though. A charged battery is like 12.6V. 12V is still like 50% charged I think.

Either way, I doubt a battery would cause a long crank unless the cranking was noticeably slower than before. Remember to fix the cause, not the symptom.

[supkev]

Turns out to be a bad fpr and dampner

[jalopi]

dampner?

[BobombETA]

Is it engine temperature dependant at all?

[supkev]

Is it engine temperature dependant at all?

I have a lower temp thermosat if thats what youre asking?