89IROCCVRT

I have a quick question. After I run my 89 305 TPI for like 30 minutes, a decently good amount of time for it to warm up to operating temp and stay there for a lil while, I turn it off, because I arrive at my destination. Everythings right. Now, when I try to turn over the car again, it takes a pretty good amount of time to start it up. When I try to start her cold, she turns over quick, very quick. But when shes warm, when she should turn over quick, it takes her a while. I dont think the engine is overheating, even though it does get quite hot. All ignition components are fine. What the heck is goin on? Thanks for any help.

Stekman

It sounds like you are suffering a classic case of the weak factory starter being too weak. Is what is probably happening is youe engine is hot (when you attempt to start it while its still warm). This better promotes firing on all cylinders. Is what happens, is the weak starter can't generate enough speed to overcome the sparking the air/fuel mixture BTDC. Because it cannot do that, it actually lights it ATDC, or while the piston is on its way down.

A mini starter is the best cure for it.

nsimmons

i'd lean more towards the fuel pump, if its cranking over fine, a hot fuel pump was the cause of a few problems for me on 2 fbodies and 1 ybody

Fire"Dutch"Bird

iTrader: (1)

dirty and/ or leaking fuel injectors.

First, try a bottle of GM Fuel System Treatment part# 12345515
available at GM dealer.

If this doesn't help, have your injectors proffesionaly cleaned, or replace them with new ones right away!

ede

i tihnk me and a few other are having a hard time understanding what you're trying to say. does it turn over just fine but not start or does it turn over slowly? if it turns over fine but not start i'd look for a fuel presure problem, if it doesn't turn over ver quick i'd look at a starter problem.

89IROCCVRT

it cranks like it does when the engine is cold....it just takes say...3-10 seconds to start it when its cold.....when warm it can take 20-60 seconds of constant cranking

Fire"Dutch"Bird

iTrader: (1)

Right, dirty/leaking injectors, very common!!

RednGold86Z

iTrader: (1)

Hmmm, for a TPI that's a bit of cold crank time too. Maybe the fuel pump relay is bad, and the oil pressure safety/bypass relay is turning on the fuel pump. With the cold oil creating higher pressure sooner than the warm thin oil, it could be possible. Can you hear the fuel pump turn on for 2 seconds at first key-on (not cranking). Mine's slightly audible.
Have you tried holding the throttle a bit open during this? How about pulling the snorkel at the throttle body, squirting a really quick shot of starting fluid, replace the snorkel, and then crank. It may help diagnose whether it's getting fuel or not. Or get a fuel pressure gauge and watch it at key on, without cranking. It should shoot to 40+ psi for 2 seconds, then drop a tad, and slowly decrease.

Good Luck,

Air_Adam

Wouldn't dirty injectors make for hard starting at any temp though?

I'd say weak ignition... maybe you need a new cap and rotor, maybe your coil took a dump... how old are your plugs, and how do they look? What do your plug wires look like?

Red Devil

What happens if you step into the pedal while cranking when it's hot?

89IROCCVRT

i put new plugs in a couple days ago, the wires need to be changed so i'm saving up for that, along with a new cap, rotor, and coil......i didn't get the chance to play with that problem at all today cuz i had to remove the axle because i rounded a lug off ....which took a good 5 hours i'll try pressing on the gas and such tmrw when i have the opportunity to...i'll try to get to it, i might not be able to...i had to take the exhaust off (muffler and tail pipes) the dumbasses who had it before installed the tail pipes in the wrong sides so now it wont hook up to the brackets correctly...and those pipes dont wanna come out of the muffler either....i'll post what happens tmrw

EDIT: i dont think its injectors, i cleaned them out decently enough but i'd assume that would cause it to screw up regardless of how warm or cold the engine is

Fire"Dutch"Bird

iTrader: (1)

After shutting down a hot engine ,this is what happens with leaking injectors.
They don't close all the way, therefor letting in small amounts of fuel, causing a VERY rich condition, the engine can't start at all.
After cranking for a long time, the rich mixture is replaced by the correct mixture, and the engine starts, it helps when flooring the pedal, because the flow inside the cilinder increases, throwing out the incorrect mixture.
When the engine is cold, there's no problem, after a curtain amount of time, the fuel pressure will drop, the leaking injector stops leaking, the fuel evaporizes, and the engine will start rightaway.

Can't explain it any better, English is not my home language, so it's difficult to explain technical stuff!!
Maybe some one else can drop in??

Fire"Dutch"Bird

iTrader: (1)

anyone?

Red Devil

'89, when you try to start it next time put your gas pedal to the floor after the first two seconds or so and see if that helps it to start.

89IROCCVRT

ok, will do

IROCThe5.7L

How does it start after the excessive cranking? I just fixed my leaky injectors, and after it would finally start, it would chug for a few seconds then resume normal idle.

89IROCCVRT

it runs fine now, but before it used to chug, not anymore though