In the last week or so I've noticed that it takes a few more revolutions to get the car to go. It runs fine but always starts the same even when it's in open loop. I've data loged the car and dont see anything out of the normal. The only thing that not in my sig. is the new plugs,wires and MSD Opti. this spring. Also there is no vacume leak I took care of that to. Any thoughts would be appreciated.

 

I've just read throught some old post on the MSD Opti. Could this be the start of it acting up?

 

Have you checked the fuel pressure? If it bleeds off to quickly on shutdown, it will make it hard to start.

Scan it for codes. A slow start might be related to the PCM having difficulty finding the low resolution pulse pattern from the Opti. If that happens, it would set DTC 16.

What do you mean by "it starts the same even when its in open loop"? The engine always starts in open loop.

 

I had a hard starting issue back in the day, the motor would crank fine but wouldn't fire right away. Turned out to be the check valve in the fuel pump bleeding pressure away after the system was pressuried when you put the key to "on" so ditto what Injuneer said, slap a fuel pressure gauge on the shrader valve and tape it to the windsheild, take a look how long it takes for the psi to bleed away and drive around with it also and see if the fuel pressure dips lowwwwww when you wot or get on her.

To fix it I just did the hatch cut fuel pump method and threw in a Racetronix fuel pump. Problem solved.

 

dont those MSD's have a way to manually alter timing with a set screw or something of the sort? wonder if maybe its off, creating low timing during cranking.

but def. test the FP first. thats easily the most common problem for long cranks. that and worn out/old plugs.

 

Injuneer, What I mean is that it starts the same cold as hot. As for the codes,I don't have a dash light on? can i read that with Datamaster?(I still have 10 free trials)

As for the fuel pressure I think that, is what it is. I have not checked it with a gauge but when I turn the key forward and let the pump stop and turn it off and back on it runs for about half as long as the first time (longer than it should, I think). I can also smell gas when it does start, and I read that it could also be an injector! How would I check that?

Thanks

My MSD has been set the same, and has not given me a problem(Knock on wood)

 

well, with a fuel press gauge hooked up to the shrader valve on the rail, it sould read, I believe 45 with the pump running, eng. off. just as importanly, it should HOLD that pressure after the pump stops running. and for a long time too. so when the pump is running, it'll read, say 45psi. then the pump stops running after 2 seconds and will settle down to say 40psi. it should hold that 40psi (been a long time since I checked fuel press on an LT1 car, could be a few psi low in my examples here) for an hour w/o dropping 2 psi or more.
if an inj. is leaking down, or the fuel pumps internal oneway valve is bad, it will start dropping immediatly and either slowly or veryfast drop to nothing. or maybe 20psi Ive seen quite a few times. the way to tell the difference w/o having the right tools, is to lift the injector rail out of the intake so you can see all the inj.s output nozles and have someone turn the key forward for the pump to run. nothing should come out. DO NOT CRANK the eng. though, fuel should spray when its cranking. just forward to the on position.

but the most common problem is not enough psi from the initial pump prime. it might get to like 30psi or 35psi but that may not be enough to start the car. it will run at that psi after its started, but needs to hit a certain thresh hold (is that two words? lol) to actually start. hence, alot of cranking for the psi to build up to a high enough pressure to start the car.

good luck
chris

 

Thanks Chris! Thats alot of good info for a back yard mech.= Me LOL! I'll give both a try. I'm not sure which one I want it to be, the fuel pump(walbro 225) on Ebay is $99.00 and I'm not sure how nuch injectors are,I'll look.

 

I agree with what the others have said. Fuel pump is most likely your problem. I had the exact same problem with my car back in the day. If I let the car sit for any longer then say, 5 minutes, it would take several more revolutions to start. If I only had the car turned off for a minute or 2 then it didnt really take much longer to start. My fuel pump eventually went out and I had to replace it. Upon replacement, I never had the problem again.