Vacuum tree

[explorer76]

When I replaced my head gaskets and put the engine back together, I don't think I hooked up all the vacumm hoses correctly on the vacuum tree on the upper intake manifold. I have a 92 ex xlt 4.0l pushrod.

Does anyone have a diagram or can explain to me which hoses connect where and to what? And If you can tell me exactly what size hose I need to replace them with? I'm thinking thats why my ex won't start.

PLEASE HELP! I need to get her running.....
Thanks in advance.

adam

 

[ExplorerDMB]

I'm not exactly sure - but I don't think a vaccum problem with cause a starting issue. Maybe a idle or rough running problem -- but it should atleast start up, unless you are just getting way too much unmetered air into the cylinders. Maybe someone with a 1st gen will chime in and say other wise and help you out. Good luck.

-Drew

 

[explorer76]

I've posted a couple other times about what my problem is and no one ever responds to it. And if they do, its not really helpful.

So, here's my problem...

I blew a head gasket. I replaced it and and all the other gaskets as I was putting the engine back together. I hooked all the connection back up and everything. Replaced the spark plugs. Went to start my ex and it turns over, but won't start and I can't figure out why. My truck has been down for about 2-3 weeks now and I need it for work. Its got plenty of gas and the fump pump is working. Any ideas?

 

[live2_4x4]

I too am chasing a no start problem and will help where I can. You say that the fuel pump is working, I assume you can hear it. But what about the rest of the fuel system, have you done a fuel pressure test at the rail? Also the IAC may be to blame (do a search on cleaning, lots of good posts and pics) or the MAF (again search for cleaning threads) see where this gets you and let me know how you made out. As far as I can tell the vacuum tree is not specific to where the hoses go ( do you have unused fittings left open?) but have you checked for vacuum? Hope this helps some............
Glen

 

[dbrewster]

Did you find an answer? I have the same issue. I need a diagram of the vacuum tree.

 

[Brian_B]

I've posted a couple other times about what my problem is and no one ever responds to it. And if they do, its not really helpful.

So, here's my problem...

I blew a head gasket. I replaced it and and all the other gaskets as I was putting the engine back together. I hooked all the connection back up and everything. Replaced the spark plugs. Went to start my ex and it turns over, but won't start and I can't figure out why. My truck has been down for about 2-3 weeks now and I need it for work. Its got plenty of gas and the fump pump is working. Any ideas?

I am probably way off base here, but did you pull the distributor to replace the gaskets? I bet you have it in turned wrong and it won't start. Been there done that a few times on various vehicles.

 

[MrShorty]

Vacuum hoses on my '92:
Cruise control
HVAC system (via a vacuum reservoir attached near the AC evaporator core)
FPR
vacuum valve on the air intake/air filter housing
brake booster
auto transmission
one capped off

then there are the PCV valve and the cannister purge line, but those don't go through the vacuum tree.

If everything is accounted for, then it shouldn't be the vacuum accessories.
Another thought: if you think it is one of the vacuum operated accessories that's preventing you from starting, then disconnect all of them and cap all the ports off. Vacuum to those accessories isn't necessary for starting the engine. I wouldn't drive it in that state, but it would be adequate for determining if the vacuum accessories are the reason it won't start.

I haven't followed your no-start saga closely, but in my brief review of the situation I didn't see any mention of checking fuel pressure or for spark at the spark plugs. Have you tried pulling codes from the computer? It seems that most no starts are from no fuel or no spark (and, to belatedly answer one question I saw in your other posts. It would be really difficult to get the ignition timing so far off as to prevent the engine from starting).

 

[TheRookie]

OK checking is easy. First check for spark at the plugs. Take one out and keep the wire on it. Hold the threads to a ground (dont put bare skin on the plug or you will be upset) and see if it sparks. If it does check the rest of the plugs. If it doesnt proceed to check the ignition system first with making sure everything is hooked up. There is a wireing connector that goes to the coil pack. Make sure it is tight.

Assuming you have spark check for fuel. Use a pressure guage at the fuel rail. If you have fuel now and spark you should have fire. There are a bunch of possibilities that could be wrong but vac hoses arent really one. They can make a rough idle, bad mileage etc but it would start. Do you smell gas at the tail pipe? if so its probably spark. If not its probably fuel. Let us know your results with fuel and spark checks.

 

[JReynaxd40]

What about the inertia switch when i changed my heads to get the engine to TDC i pulled the plug for that its on the passengerside floorboard area... Also there is a resetswitch on top of it so it could be popped. I think that would shut offduel pump tho. Sorry