SO. I just bought an '87 iroc z with the l98 5.7 tpi in it.
It has 87xxx miles on it and the guy had no idea what to do with it.
He had driven it daily after buying it from a Mercedes enthusiast...

It stopped starting on him, so he towed it to his garage and there it sat.

He ended up selling it to me for cheap, so here i am. It wont start.


WHAT IVE CHECKED SO FAR:
The car does not have a VAT system. so thats ruled out

The car wasnt getting fuel, so i bypassed the relay, and the pump kicked on.
Bought a new relay, so thats also ruled out. primes when key is turned

I have good fuel pressure to the rails, so im assuming its not an issue with a clogged filter, or bad regulator

I just bought a NOID light set, and i AM getting Injector pulse.



WHAT I HAVE NOT CHECKED:
I have not checked any sensors, MAF, CTS, Oil pressure, etc.

I have not checked for spark, however, the car tends to pop, backfire out of the intake when cranking. So, i assume its getting some sort of spark.


I have an aching feeling its got to be an issue with the ignition control module, or pickup.

Any help would be MUCH appreciated.

 

Check the fuel pressure at the fuel rail, it should be ~42-47 psi when priming. Leave the pressure gauge attached then stop cranking the engine and note how quickly the fuel pressure drops. If it doesn't hold pressure for at least 20 seconds then your injectors may be leaking.

Also check the base timing, hopefully around 6 degrees before TDC or as noted on your emissions sticker under the hood. To check the timing you will have to disconnect the brown wire connector above the heater box, then have a friend crank the engine while you look at the timing marks on the crank with a timing light.

 

thanks for the input!

Gotta yank the distributor this weekend to replace the pickup...even if thats not the issue, i may as well....

So i guess ill set the timing after i do that....

If anyone has any ideas, im totally open for input.

 

UPDATE.

So at this point, ive replaced the Fuel pump relay, the ignition module, the distributor pickup, the plugs, the plug wires, and the distributor cap.

I set the motor to tdc on the number one cylinder and dropped the dizzy back in correctly.

I checked for spark: Yes
I checked for fuel pressure: within spec
I checked for injector pulse: yup

Im scratching my head at this point. ANY IDEAS?

Any help would be of much thanks!

 

i have a 87 iroc 5.7 tpi i just changed the fuel pump n it still wont start... help!! plz... it only starts if i keep puttin started fluid n as soon as i let go off that fluid it shuts down.. help me out plz

 

Check the FPR. Unplug the fuel rail near the intake and then have someone assist you with a cup to catch the gas in case it is not the Fuel pressure regulator. Turn the ignition to on but do not start the engine and see if fuel comes out. If it does then you need to check for spark.

 

thanks ill try doing that today as soon as i get a lil light,, what else can it be tho? it turns on while i spay the fluid then i stop n it shuts down right away.. can it be the injectors or relaigh?

 

Its not getting fuel that is why if you spray the intake it starts and runs, when you stop it dies. Not getting fuel. fpr, fuel pump fuel filter fuel line. Concentrate there 1st.

 

thanks so much, im no mechanic n said he be coming in 2 days,, now is that somethin i could? do checkin the fpr if so can i briefs easy steps

 

Do you have any sort of picture or pictures of where that would be located? It is very tough to try and walk someone through disconnecting fuel lines if the person is unsure of what they are doing. Plus there is a small plastic clip in the line you disconnect and if you break it you are SOL

 

My advice:
When you turn the key, the fuel pump should prime for a couple of seconds.
You will hear it. If you dont, its most likely the fuel pump relay being blown.

The fuel pump relay is located on the firewall near the brake booster.
http://www.iroczone.com/forums/viewt...hp?f=1&t=17212 theres a pic half way down the page.

On the passenger side of the fuel rail there is a schrader valve with a screw on cap used to test fuel pressure.

Pull the cap off, and push down the valve pin. if no gas squirts out, you got no fuel.

 

Have you ruled out the timing chain jumping a few teeth? Since you already pulled the distributor out, you'll have to pull the driver's side valve cover to check.

Edit: Sorry for some misinformation above.

You'll need to pull the passenger side valve cover and watch the No.6 cylinder rocker arms. As you rotate the engine past TDC for No. 1 cylinder, the exhaust valve for No. 6 should be opened; as you pass TDC (No. 1) it should close and the intake should start to open. If not rotate the engine 360 degress until the timing mark comes around to TDC and check the valve action on No. 6 again.

If you don't see the No. 6 valves "rock" as you pass TDC, most likely the timing chain has jumped.