can something in exhaust cause engine not too start? 1ZZFE

[wiso]

I got a weird problem with my ZZW30. but this a more a general question than specific to that car

Car was driving fine one night then went to start it next morning all the engine did was crank over. It did sound a bit slow so new battery was first on the cards. Then checked for fuel and spark, all good (same fuel has been in there over a week and has run fine every day). Checked timing/chain to make sure all still in time. checked all fuses and relays. At a loss and with a slight inkling I dropped the exhaust.

So with just the headers on the motor no more the car started and ran. So I thought easy. Cats collapsed and blocked up. (on a ZZW30 the cat is appart of the exhaust, a section about 1m long with 2 bends either side so you can't physically see the cat unless you cut it out.)


Now to the problem. I got a new cat, came off another car that ran fine. Bolted it onto mine and what do you know the car does not start again. So can anything in the exhaust (muffler mostly) collapse blocking the flow?

Tomorrow I will try and unbolt the section between the cat and muffler to see if it starts with only up to the cat connected. Ran out of day.

[river]

Hi,

If the exhaust is nearly or totally blocked the engine will not run. The engine is like an air pump - it sucks it in, burns it up, and pushes it out the exhaust. If it can't get anything out the exhaust then nothing's going to be able to get in.

Air, being a gas, is fairly compressible, so I would of thought you'd at least get the engine firing then die pretty quickly.

Interested to know what it is and what you find. Keep us posted.

seeyuzz
river

[oldcorollas]

mufflers can collapse.. or get blocked up with cat that has blown out..

no-one stuffed a potato up ya pipe?

[wiso]

on zzw30 precats fail usually filling the main cat with ceramic blocking them. hence why i thought my cat was blocked. but it may be in the muffler section as this is now the only common item.

had a look up there can't see anything in the end of the pipe.

[NME308]

A certain police dog squad officer from my past can certainly vouch that a blocked exhaust prevents a motor from starting...
I 'think' a potato 'may' have ended up being responsible...

Cheers,
Jason

[Harreh]

Why dont you unbolt the muffler from the cat section and go from there?

[river]

Hi,

Nice one Harreh. Come up with another sensible approach to fault diagnosis and you'll be banned.

seeyuzz
river

[wiso]

Harreh I said I was going to do that today. And I did. No good though. actually when trying it I blew exhaust gas out the intake gasket

so unbolted at headers again. engine starts again.

turns out the motor is that low on compression that with the exhaust bolted up the back pressure chokes it so it does not start, without it it flows free enough to run. Like shit but runs.

Good that I got to the bottom of it. Not a good result though. Thanks for those who helped.

[river]

Hi,

Crikey! Yeah, much better result to have a blocked exhaust.

Compression has got to really be fucked then. I'm surprised it would even start without the headers if it was that low. Must run like a dog and sound shite.

seeyuzz
river

[wiso]

yeah ran like a dog but still ran, actually it's running on 3 cylinders.

cyl1 0psi, cyl2 158psi, cyl3 145psi, cyl4 153psi

[Dan_k36]

Do u live some where we're it is cold and have you changed your oil in the last week, working for the rac I have seen that many times, lifters don't like to do there job and won't start,

[xero]

I think one of your vavlve might be stuck man, either way it's a fucked situation to be in.

[wiso]

you know, i know this really awsome dude named hocker. and hes so good with cars he is usually right.

in this case the second intake valve is seized full open. with comp results like the other 3 though they are approaching the end of their life at min 145psi

[MR22ZZ]

I've got a full set of operable 2ZZGE valves and springs you can have Joel.

No idea if they are compatible but your welcome to them

There's also a complete set of stem seals to go with them as well as I bought a second set not knowing there was a set in my head rebuild seal kit (funilly enough)

Conversely, I also have a set of headers designed for putting a 2ZZGE into a ZZW30

[xero]

you know, i know this really awsome dude named hocker. and hes so good with cars he is usually right.

in this case the second intake valve is seized full open. with comp results like the other 3 though they are approaching the end of their life at min 145psi

you know im not always right, but when i am...


...i brag about it.


also get that stuff from dylan, that should go back in easily enough.