wayshegoes

So have the car out of storage again, have the long crank issues again

from doing more reading i have some questions,

if my fuel pump relay was bad, then would i hear the pump prime when key is turned?

is there a way to test the oil pressure sender, the one by the oil filter?

I am wondering if the relay is having issues and then using the oil pressure sender for power, waiting for pressure to build, before starting causing long delay

I always have 0 oil pressure until it starts, then sits at 50 at idle, using a mechanical gauge as the one on the digital dash dont work

after it starts i can shut it off and restart right away, let it sit for a few hours and back to hard starting

would really like to solve this

Pro

How to test oil pressure switch

Hawgtied

Following closely.


Mine will fire right off when it has been sitting for a few days but when it has been run a little while, I have to lay into the starter pretty good. Otherwise runs like a spotted ape.

wayshegoes

Thank you for the video


to test the oil pressure switch can i disconnect the wire harness and short it as if it was getting the 4 psi to make it closed, what pins would i jump? then try to start, and in theory if this was the problem it should start right up?

Pro

Orange and grey should complete the circuit, telling the pump to run. So I believe you would jump those. The other wire goes to the gauge.
You'll know if the sender is bad for sure if you disconnect the pump relay while the car is running. The sender is a backup to the pump relay to turn the pump on. If the engine dies when you remove the pump relay, then the sender isn't sending it's signal to the pump to turn on.
There was a guy on this forum for some weird reason put a toggle switch on those wires and removed the fuel pump relay. That way he could turn the pump on and off manually. He wanted to wait until the oil pressure got high enough for him before he flipped on the fuel pump. I dont understand why - pressure increases when the motor turns over anyway...

wayshegoes

I pulled the fuel pump relay with car running and it kept on running, so oil pressure switch is working

still hard to start cold, but once started it fires up no problem after, till it sits overnight and next morning long cranking again


2 hours later car has been off, fires right up

4 hours later, 4 second crank and had to give a lil gas after it caught

once i get my gas gauge back i will check pressure while cranking again

Pro

You may have the same problem I do.
- Hook up fuel pressure gauge (and release all pressure)
- Turn key and see how fast/high the pressure rises before prime shuts off.
If it doesn't jump to 35-45 (or whatever the spec is) quick then the pump may be getting weak. Mine does this. After it spins for a few minutes, its like it's warmed up and good to go for another couple of hours. I think it's a symptom of these old gear style pumps going out.

This is my car currently and exactly what I'm talking about
Sometimes it will barely get past 20
Eventually the pressure will build to to 40, 45 I cant remember. And if I release the pressure, and turn the key again, it jumps straight up to 40-45 instantly. Its only a matter of time before it gives up entirely.

tom86iroc

iTrader: (1)

when you turn the key u should hear the pump come on if not when you crank it it bypasses the relay when it senses oil pressure and will start i had a bad relay years ago when your cranking the motor watch the oil gauge it 'll just start to move and then the motor will fire up

wayshegoes

my apologies for taking so long to reply, just got my gauge back after i let someone borrow last year

gauge connected, turn key, pump primes and gauge instantly jumps to 50 and then as soon as pump stops priming it drops quickly

turn key off and back on, pump primes, crank car, gauge is at 40-41 while car is cranking, takes 3 long cranks and car starts, idle gauge is showing 36-37

im going to up my running pressure by adjusting my FPR as 36 is a bit low?

so to me it seems like it has pressure while cranking, suggestions please



also, dont lend out tools, come back missing pieces and broken, noticed my gauge now leaks when connected to rail, made sure it was tight, but still a small bit of gas leaked out

Pro

The pressure is fine, but pressure disappearing after the prime stops isnt always. How much does it lose?
You could have injectors not working properly. You might want to OHM test the injectors. If any are off then just throw them all away and get new ones or refurbished from southbay.
Then figure out where the gas is going after prime stops. Pinch off the return line, prime, pinch off feed line while its still priming. Watch fuel pressure. If it drops then I cant think of anywhere else the gas could go except out open injectors.

wayshegoes

I have done leak down test in the past, last year was last one, with the return line pinched pressure slowly drops

the injectors were replaced about three years ago, bosch III, only thing is the were not purchased from southbay, i did have a couple that were originally replaced due to leaking..........

i will ohm test tonight, have been thinking bout just replacing them with ones from southbay

from leak down i did in the past i was directed to replace the FPR, i had already replaced due to fuel leaking into plenum, then replaced again with adjustable from southbay, thinking it was causing the quick drop in pressure, but made no difference

i would love to finally get this resolved, would be nice if it would start easy again

wayshegoes

all injectors showing 16.6 when checked -- so this means they are good?

any suggestions as to what i can try next?

wayshegoes

So my thought is this is cold start related

after its started, it restarts no problem, but once it sits for 5-6 hours the long cranking returns


so, i am looking for a 89 TPI 305 5 speed memcal, i have my chip in a adapter that has set the 9th injector to off, wonderting if it actually is set though

temp sensor was replaced, will get out my cable and do some data reading to see what it is on start, and if it increases

Tuned Performance

iTrader: (92)

The 89 programming still has a long craning time. It’s set to enable the injectors after one revolution of the engine. Although it seems to take 3-4 revolutions to really start.if the ninth injector is still present it can. E used in conjunction with the 89 tune to help aid in cold starting.