new head gasket --> now won't start!

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apampe

New member
So I just replaced my head gasket and now I'm getting nothing. It cranks well, but no signs of starting... no popping or mis-timed sounds whatsoever. So either fuel or spark is non-existant.

Spark (i'm convinced this is ok)-
- Spark is in the wires, as a timing light blinks when hooked up to any 4 plug wires
- So the only possibility i see is plugs. old but worked before I began HG (and once agian there's not any sign of it starting on any cylinder)

Fuel
- Fuel pump is on when cranking, and when I jump it at service plug, sure enough, fuel lines bulges some and fuel is coming back through the fuel return line (filter and pump ok?)
- So, either fuel pressure is wrong, which I would suspect a hard start
- or the injectors aren't turned on...

the Toyota Service manual says you can listen to the injectors with a sound scope (or a screwdriver)... what do they sound like when operating normally?

Also, I don't smell fuel in the exhaust, but I have yet to get someone to crank for a while as I'm smelling.

So I'm a bit stumped... what should I check next based on probablilty of cause, and ease of checking? Fuel pressure regulator, a relay, vacumn line... I don't even know what else!?!?!? Is there anything that would cause the ECU to just not fire the injectors?

Thanks guys.
 
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apampe

New member
Yeah, crank at cylinder1 TDC, with cams lined properly (dots on top). Then I just looked at the vales, while hand-cranking. It was correct.

I'll check agian, but I believe ther'd be some backfiring etc. I haven't heard the sligntest hint of an explosion in there.
 
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Andy

Member
Distributor? It can go into the head 180 degrees off and you would get spark, but at the wrong time....

At TDC the "rotor" should be pointing towards the #1 plug contact inside the distributor, ie. lower left, 7-8 oclock

Andy
 
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apampe

New member
I just now double-checked this.

On mine, there's a slot in the cam, and a ridge on the distributor that fits into the slot. It first appears that it can be off 180 degrees, but this slot is slightly off-center, so it only fits one way.

I will visually check the rotor position when I crank it to TDC and recehck all the timing.

I'm double-checking all this, but am I wrong in thinking that you'd hear at leats some sort of firing even if the timing was completely out of wack. In the past I've always head firing noises when the timing is incorrect, either ill-adjusted or completely off.
 
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Simba

New member
Crank it a bit with the plugs in, then pull one out. If it's soaked in fuel, injectors are firing, if not, not. Check the resistor pack, ECU for codes, wiring, etc, etc.
 
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RWDragoon

New member
You can buy an injector diode for like $6 at any parts store.. just unplug any injector and plug the diode in and crank over if it blinks then your injectors should be firing (unless injector has failed but probability of 4 failures is very low)
 
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BoostedBlueToyotas

New member
If the intake cam is timed correctly (dot in correct place) then the distributor is also correct since it can go in only one way (and it sounds like the cams are right).

edit: And he has the crankshaft pulley set to TDC then he should have
the static timing correct.
 
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Mafix

New member
i woudl go and check all the little plugs on the manifold. you may have the 4 wire ground connector on the back of the intake disconnected.
 
A

apampe

New member
New developments. So it did manage to idle it for about a minute. I had to crank for a while and it eventually came around and started (very slowly though). It begain where you could tell the starter was under less of a load, then less, until it was idling on it's own at 300 or so, then sped up to normal. 1 minute of solid idling. Sounded great! It died as i tried to adjust the timing with the light and then only sputtered when I tried to start it agian. It just wouldn't go agian. Could this be a problem with the cold start injector? I've double-checked it's plugged in right, Maybe I'll buy a tester and see. Or does the cold-start injector work differently (like voltage instead of a pulse width)?

That was last night, today I get nothing. And I don't know what caused last night. All I did was:

-check the resistor box, all read about 6 ohms.
-make sure the 4 wire ground was bolted up (was, but I was convinced you were right, I'm going to go searching for more ground wites now...)
 
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Mafix

New member
cold start is not needed. it really sounds like the timing is off. check the cams and make sure the cam gear did not snap the dowel pin.
 
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apampe

New member
So it's finally running well. Ended up being a wet engine compartment. I have a custom hood vent, that usually causes no problems, but since it sat in the rain for a while, things got a little wetter than normal.

I got a tester for the injectors and they weren't firing. The more I left a space heater under the hood, the more they started firing!

Thanks for all the help! That was a confusing one.
 
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ironpanther

New member
for further refference you mentioned the sound scoping the injectors. This can be done with a screw driver. By firmly placing the tip of the screw driver against the body of the injector and putting your ear against the end of the handle you should hear the clicking of the injector firing. Make sure you are not touching anything else because this works by carrying the vibrations of whatever you are touching through the screw driver. So anythign else it is touching at the same time can cause noise.
 
R

Red Rabbit

New member
i kno this is a rather old topic since it is from last year :lol: but anyways, im having a similiar problem with my GT daily driver, we just did some extensive work on the 5sfe with it out of the car, timing is dead on when the new head was put on and all the wiring seems fine right now. New plugs, new t belt, new plug wires etc... here is what we got car will crank forever and end up starting but runs crappy, and dies and will not rev at all. Car has erratic injector signal and u can hear a clicking noise actually coming from the pcm it seems. thoughts anyone?
 
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