gearheadjlm
New Member
- Joined
- Oct 18, 2008
- Messages
- 39
- Reaction score
- 1
- Points
- 0
- Location
- Jacksonville NC
- Vehicle Year
- 2003
- Make / Model
- FORD
- Engine Size
- 4.0 SOHC
- Transmission
- Automatic
I need help diagnosing a major problem, 4.0 SOHC
About two weeks ago I bought a 2003 Explorer with a 4.0L SOHC. I recently planned on doing my usual thing of fresh fluids, filters, plugs, and anything else it needed. So, after finally getting a couple days off, I decide to replace the valve cover gaskets due to a minor leak. So, first I decide to add some Seafoam to the engine, about a half a can to the oil and a half can through the brake booster. I've used that stuff on dozens of vehicles with pretty respectable results.
After running it and it smoking a bit as the Seafoam does, I let it cool down and started disassembling to get to the valve covers. After relaxing with a few beers and taking my time, I put new valve cover gaskets, intake manifold gaskets, throttle body gasket, new spark plugs, wires, air filter and thoroughly cleaned everything. Before changing the oil/filter, I figured I'd start it up just to make sure everything was good. Well, it wasn't.
It'll start and idle, but the second I tap the throttle it dies. A vacuum gauge reads a steady 8, indicating a likely vacuum leak. So, I triple check all connections and everything looks good. I sprayed starting fluid, everywhere, and no increase in RPM. I do hear a high pitch noise from somewhere around the throttle body/back of the engine. But do not see or feel anything wrong.
So. I decided to go get myself a big fat cigar, despite me not being a smoker. I puff as much smoke into the intake (through a hose where the brake booster goes on the intake) and am getting a small amount of smoke rising up somewhere around the throttle body.
I took the intake off again to check to see if an intake gasket was my problem, seemed good to go, checked everything around it, and reinstalled it. Annnnnd still the same problem.
I am not throwing any codes, at least in the few minutes I've let it idle. I took off all the vacuum lines and checked them for cracks and integrity, they are all good to go.
So my ultimate question is this: what the hell could be leaking so bad to make it lose so much vacuum and run so poorly? What am I forgetting? Could the Seafoam have messed something else up? Why am I not throwing a code?
Any ideas guys?
About two weeks ago I bought a 2003 Explorer with a 4.0L SOHC. I recently planned on doing my usual thing of fresh fluids, filters, plugs, and anything else it needed. So, after finally getting a couple days off, I decide to replace the valve cover gaskets due to a minor leak. So, first I decide to add some Seafoam to the engine, about a half a can to the oil and a half can through the brake booster. I've used that stuff on dozens of vehicles with pretty respectable results.
After running it and it smoking a bit as the Seafoam does, I let it cool down and started disassembling to get to the valve covers. After relaxing with a few beers and taking my time, I put new valve cover gaskets, intake manifold gaskets, throttle body gasket, new spark plugs, wires, air filter and thoroughly cleaned everything. Before changing the oil/filter, I figured I'd start it up just to make sure everything was good. Well, it wasn't.
It'll start and idle, but the second I tap the throttle it dies. A vacuum gauge reads a steady 8, indicating a likely vacuum leak. So, I triple check all connections and everything looks good. I sprayed starting fluid, everywhere, and no increase in RPM. I do hear a high pitch noise from somewhere around the throttle body/back of the engine. But do not see or feel anything wrong.
So. I decided to go get myself a big fat cigar, despite me not being a smoker. I puff as much smoke into the intake (through a hose where the brake booster goes on the intake) and am getting a small amount of smoke rising up somewhere around the throttle body.
I took the intake off again to check to see if an intake gasket was my problem, seemed good to go, checked everything around it, and reinstalled it. Annnnnd still the same problem.
I am not throwing any codes, at least in the few minutes I've let it idle. I took off all the vacuum lines and checked them for cracks and integrity, they are all good to go.
So my ultimate question is this: what the hell could be leaking so bad to make it lose so much vacuum and run so poorly? What am I forgetting? Could the Seafoam have messed something else up? Why am I not throwing a code?
Any ideas guys?
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