Need some help with starting issue

dickersonam23
Posts: 6
Joined: Mon Apr 14, 2014 7:36 pm

Need some help with starting issue

Postby dickersonam23 » Tue Aug 18, 2020 5:07 pm

16v 4age w/TVIS swapped SR5

I’m having issues with getting my 16v to run after changing the water pump from it cracking. The engine has some work done to it but no tune as of yet, however it ran with a ghetto rigged wire from the throttle body to the inside of the car to act as a “choke” to get it started (because of the tune). It ran fine before the water pump blew. Anyways... It sat for a few months before I got around to it. After changing the water pump, I went to start it up, it cranked over but wouldnt run. I hit with some starter fluid and it started but only ran long enough to eat all the starter fluid then died. I checked my spark plugs, and they were good, swapped out the dizzy cap and all spark wires cuz they were kinda f**ked up. I checked to see if I had good fuel pressure, which checked good so it’s getting fuel. I’m thinking it’s cuz it needs a proper tune but I also don’t see why I’m having issues to get it to start up. If y’all have any ideas or thoughts, I’d greatly appreciate it. Thanks.

Nick94tt
Club4AG Expert
Posts: 253
Joined: Mon Jan 13, 2014 9:43 am

Re: Need some help with starting issue

Postby Nick94tt » Tue Aug 18, 2020 8:10 pm

The whole thing sounds rigged to the point of pre-failure, but I'd guess injectors. Works in progress always suffer when waiting. (See the coupe in my driveway, lol)

Odds are the fuel tank is rusty and the lines/filter are already half clogged, but sitting is death for injectors with alcohol mixed fuels. Can try gently tapping them while pressurized (or verifying they're even functioning with a stethoscope) , or pull them and clean / send out for cleaning.

They also may not be getting a signal to activate in the first place. Noid light or multimeter will help confirm. Might be as simple as a missing ground.

If you pull them, make sure to have new injector kits ready (seals and orings) as if they're stuck enough to fail the seals are probably gone too.

Use gas or oil to lube the new seals. Silicone will kill your O2 sensor. ^_^

You'd have to get pretty wild with compression changes and head work to get a 4age to not at least try and run with stock injection at idle.

Hope it helps.

dickersonam23
Posts: 6
Joined: Mon Apr 14, 2014 7:36 pm

Re: Need some help with starting issue

Postby dickersonam23 » Tue Aug 18, 2020 11:15 pm

Thanks for the response, I’ll have to check the tank to see if there is rust and clean the lines. I had thought it could be an issue with fuel and I had changed the fuel filter already and my next rep was to check the injectors. I had checked my compression and it was all good. When I rebuilt the engine I had put in 256/256 cams, new valves and springs, have 81.5mm pistons and rods. I changed the fuel pump and injectors which was about 4 years ago. I’m running the stock ecu with plans to put in a megasquirt because it was rough on initial start up due to a lack of fuel however once warmed up it ran just fine. So I was running it on the stock ecu while waiting to get a megasquirt or something to properly tune it.

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jondee86
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Joined: Fri Jan 11, 2013 10:21 pm
Location: Wellington, New Zealand

Re: Need some help with starting issue

Postby jondee86 » Wed Aug 19, 2020 12:37 am

Engine needs three things to start... air, fuel and spark. If it ran off starter fluid then
you have spark. If you had to use the "choke" before, you will likely need to use it now.
Opening the throttle plate a fraction allows more air into the engine. And, on an AFM
engine letting more air into the engine opens the flapper thing inside the AFM a bit more
which tells the ECU to add a bit more fuel... all of this is good for starting :)

Providing the fuel system is working then your cold start injector should squirt fuel into
the manifold while the engine is cranking. It usually supplies enough fuel to get the
engine running if the throttle is closed... or at least cause some popping and banging.
You can check the cold start injector is working by pulling it out of the manifold, putting
the business end in the neck of a glass bottle and cranking the engine. There should be
a decent continuous jet of fuel. It stops squirting when you let go of the key.

If you get fuel out of the CSI then your fuel system is working. The next thing to check
is if the fuel pump runs when you turn the ignition ON and manually open the flapper
inside the AFM. There is a switch inside the AFM that turns the fuel pump ON when the
flapper opens some small amount. If someone has been farking with the AFM that may
not be happening if you are cranking with a fully closed throttle plate.

If all else fails, try keeping the engine running with starting fluid for 20-30 seconds. If
the injectors are gummed up (which is likely) the ECU will be pulsing them while the
engine is running and that might possibly loosen them up... if you are lucky :)

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.