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A few days ago it sounded as if I cracked an exhaust manifold (ticking sound from right side) In the last week I've noticed I was losing power, especially at higher RPM's

Tonight driving to work cruise at 65 hit an incline and van started to slow, at about 55 it down shifted (high RPM's), when it did it went from 55 to 45 like no one was on the accelerator. I disengaged the cruise when the throttle came back up and the van upshifted I was able to nurse back to 55 with about 1/4 throttle.


I've noticed it accelerates better if I ease into the throttle and never go beyond 3/4 travel

SO what's up, maybe a plugged CAT

1994 E350 174000 miles 7.5 ltr

ALSO THE VENT FAN STOPPED TONIGHT; I DON'T THINK THEY'RE RELATED

 

sounds like a cat to me

 

Did you confirm it was not a cracked exhaust manifold?

What cats are on it after 14 years & 174K, originals?

How much heavy hauling has it done?

Be aware that many "ticking sound" causes are valve or piston issues. Pulling the Dog House & using a mechanic's stethescope should isolate the source of the "ticking". Some misfiring might also sound like "ticking" including cross firing from failing plug wires.

Cats that break apart inside usually rattle, "plugged" ones don't make me think "ticking".

 

I haven't pulled the dog house yet. The ticking sounds external, it's right under the passengers feet. I know that Ford vans have manifold issues. I'm not sure if it's spark (I'll check with the dog house off and the lights off to see if there is arcing). I really only notice it when I'm on it, coasting or idling you don't hear the ticking.

It hasn't done much hauling in it's life.

I should add that when I get on it it sounds like a big 4bbl opened up (it EFI), but you don't feel any performance change. If you feather the throttle while cruising it almost sounds like a turbo winding up.

This van used to get up and go, now it's a dog. The ticking started 3 weeks ago and has gotten louder, the power loss just started 1 week ago.

One more thing that vent fan stopped again last night just as the vans performance died off. I'm not running the a/c just the vent and fan.

I'll crawl under tomorrow to hit the CAT and see if it makes noise. I had a Mustang GT that had a CAT fail and it felt just like this, minus the ticking. Could a failing CAT produce enough back psi to crack a manifold or blow the gasket?

 

Regretably, this once reliable way of diagnosing bad plug wires is much less useful w/modern high V ignitions. When resistance wires go bad the cross firing often occurs inside the cap. Many good mechanics recommend changing wires when you change plugs & can be very fussy about which wires to use.

Good luck crawling under & hitting the CAT.

 

Well I got home and was able to beat the CAT with a hammer. Initially I didn't hear anything than.....a thunk. It wasn't a rattle, more like one loose piece in there. Anyway the van is running 100% better. The ticking is only there under HEAVY acceleration, otherwise gone.

So tomorrow I guess I'll be cutting off the CAT all together.

So where should I go for a Y adapter to extend the exhaust pipe????

 

Just kidding about cutting it off!!

Looking for a new one is a bit confusing. I'm finding an Eastern 30259 (exact fit) for 264.42 but there is also a Eastern 70531 for 92.58 (it's not an exact fit).

So, I'm a bit lost. I'm sure there's more someone point me in the right direction please.

What inputs/outputs are in the CAT.


Just a review:

E350 1992 (ya, I know I put '94 my bad) 7.5Lt. VIN code G for engine.

 

You realize that you can ruin a perfectly good "CAT" if you "beat" it "with a hammer"?

Can we presume the cat's original, there's no cracks in exh manifold & there's no reason to suspect worn out plug wires?

 

Yes I'm aware. In the mean time I did not have enough time to pull the dog house between chuch, wife going to work and me working...and all those kids......

Anyway beating it might have been a bit harsh. I hit it with my fist first, with out thinking I had just driven 30 miles (dang that was hot). So out came the hammer. 2 light taps and it was making noise. The van ran much better. Couple pot holes latter all of a sudden we're ******* out again Pull over tap with a hammer and you could hear the sound of the exhaust change and see the tail pipe actually start to move a bit b/c of the higher flow.


CAT looks original. Wires and plugs were new about 10000 miles ago. Still not 100% about manifold, but will put a new CAT in before I swap out an exhaust manifold.

So any ideas on where to hunt for just the right CAT? As I said there seems to be ALOT more options than I thought out there.

 

several options
buy cheap cat and have it welded in at a shop
buy expensive factory original and bolt it in
or the incorrect way of pull the cat, bust up the insides and dump out then reinstall

 

Well I guess option 1 is the way to go. My local shop will do it for cheap. Of course "option" 3 would work

 

I've never had a cat go bad, not to say that isn't your problem, but how about your Throttle position sensor? If its going bad ( not giving enough voltage to injectors, therefore not enough fuel...........or possibly a fuel filter???

350k+on a '92 w 5.8 liter, original cat/y-pipe.
150k+on a '98 w 6.8 liter, original exhaust system.
previously, a '92 e-150 w 5.0 w 200k, original cat/ y-pipe.
and an '85 e-150 w 5.8 200k, original cat/ y- pipe.

John

 

In regards to the vent fan, the vent / a/c mode fails to defrost if the vacuum system has loss of vacuum. My '92 van has this problem. I just back off on the throttle till vacuum system pulls doors back into place and then ease into throttle again. When I'm driving up hills I just grin and bear it. and turn off rear blower as rear a/c goes to heat mode! I don't have any performance issues when this happens but it could possibly be such a large leak on your van that maybe it is affecting your engine in some way..........

John

 

That makes perfect sence. I don't think it's a leak though, jst the engine being choked off.

Fuel filter is new I'll check the TPS.

But the CAT is shot.

 

It's fixed. Local shop was able to remove the CAT with out damaging the flange, O2, or EGR(?) tubes. Was able to slap another one on in less then 20 minutes.

BOY-O-BOY did it sound good with out the exhaust!!!! Maybe I should look into a glass pack