Class C 1994 Passport by Cobra engine troubles

[jcb47769]

Hi everyone, my wife and I are new to this. We just bought a 94 Passport by Cobra, and on the drive home she started acting up. First off we lost the alternator belt, and didn't find out until we arrived home (replaced it now). That isn't the problem now, but I mention it in case it could be connected to our other problems.

First problem is lack of power on uphill. RPMs go up no problem, but it feels like we are actually slowing down. If the pedal is floored, it won't shift at all, just races the engine and no power. You can slack off the gas, and she changes gear, but still really laboring over even the slightest hill. We can't realistically get over 50 mph unless it's downhill.

Second problem is a peculiar whistling sound from under the hood. I haven't been able to locate it yet, but it only happens when you hit the gas - nothing at idle, and it goes away momentarily when the engine shifts and RPMs drop.

Help! We don't know if we just bought a lemon, or if this is something we can fix, and we basically gave all our money to buy the RV, so exploratory surgery by a mechanic is likely out of the question. I'm mechanically inclined (I've replaced inboard engines in boats, and some transmission troubleshooting, etc) but not a mechanic.

1993 ford e350 chassis, 27k miles

Thanks!

[jcb47769]

Krusty wrote:
As far as your lack of power, it sounds like either a plugged up catalytic converter, or the fuel pump is failing. To determine if the exhaust is plugged, you could remove the oxygen sensor from the exhaust and drive it under load to see if some power is restored. It will of course be much louder. You could also install a pressure gauge to measure the amount of back pressure.
To test fuel pump, connect a fuel pressure gauge to the Schrader valve and drive it under load. Fuel pressure should be above 35 psi and not drop below 30 psi under load. If you haven't already, make sure to check your air and fuel filters first.

Looks like this is the next step. Got everything bolted back together and took her for a test run, and the exhaust manifold is glowing red. Also, a funny sound from the top of the engine when she is working hard to go up a hill, loud and kind of like a 2-stroke motor. Also found another small exhaust leak on the manifold on the starboard side of the engine, where the manifold bolts to the engine. Really feeling like a clogged cat. Could I rod out the cat to test it? Or is that going to mess with some kind of sensing system. Obviously not a long term solution as it's illegal to drive it like that I'm pretty sure.

[Krusty]

As far as your lack of power, it sounds like either a plugged up catalytic converter, or the fuel pump is failing. To determine if the exhaust is plugged, you could remove the oxygen sensor from the exhaust and drive it under load to see if some power is restored. It will of course be much louder. You could also install a pressure gauge to measure the amount of back pressure.
To test fuel pump, connect a fuel pressure gauge to the Schrader valve and drive it under load. Fuel pressure should be above 35 psi and not drop below 30 psi under load. If you haven't already, make sure to check your air and fuel filters first.

[jcb47769]

Victory of sorts. Drilled a small hole next to the broken piece of easy out. I
Used a punch to knock it loose. Drilled the bolt out. Now I just need to drill it out to size and replace the bolts. Thanks for the help and moral support

[ron_dittmer]

rgnprof wrote:
Bolts were already broken - really loud until it warmed up some. In my experience, every single bolt/stud has been broken off pretty flush to the head...

I suspected they had sheared at the head. That was always the case with the Pontiac Fiero 2.8L-V6 engines I worked on. I spent many hours as a contortionist getting sheared studs out of those engines. Those manifolds were piped but they were not headers. I think they failed because the pipes would warp from the heat causing undue stress on the bolts. I wonder if a cast manifold would have been less trouble.

[rgnprof]

Bolts were already broken - really loud until it warmed up some. In my experience, every single bolt/stud has been broken off pretty flush to the head...

[ron_dittmer]

Ryan,

Did you break bolts or were they already broken and you simply discovered the hex heads missing? When they break, do they break flush with the head or is a stud remaining?

Ron

[rgnprof]

There's a case right now where one of our OP's found two broken exhaust manifold bolts. Worked about a week and ended up pulling the head to go to a shop. That led to a valve job, bolt hole oversize, etc.

As JD put it so eloquently, and delicately 🙂 - I'm the "case". Wow - what a mess - twice for me actually as I've had to replace broken exhaust manifold bolts on both sides! I have learned one thing - next time I will just pull the head. I know it sounds like a lot of work, but actually, it's much easier than you think and FAR less time consuming. I mean unless you have all the rights tools, tons of experience and SKILL - drilling these bolts is a nightmare!

Good luck!

ryan

[jcb47769]

Some success, 2 carbide bits later I'm nearly through the bolt steel. Starting with a smaller hole next to the hard steel easy out, hoping to dislodge it next. I have no intention of tearing apart other areas. Road salt has rusted the manifold bolts and even the exposed portion of the spark plugs quite heavily

[j-d]

OP, Let me state this constructively but in the strongest possible terms:

This project is heading for BIG TROUBLE. If you can get that broken stud out, then I support what Dittmer is saying. LEAVE the rest alone! You go trying to get that manifold off to take it to a machine shop, etc. the odds are WAY against you getting all EIGHT manifold bolts out. There's a case right now where one of our OP's found two broken exhaust manifold bolts. Worked about a week and ended up pulling the head to go to a shop. That led to a valve job, bolt hole oversize, etc.

Part of why I'm saying this, is the amount of rust I'm seeing in the picture. Being in New England where they salt the roads. Rhode Island where the air can be humid and salty.

Our OP brought a mechanic to the RV and he couldn't get the broken bolts out of the head. Find somebody who specializes in stuck bolts and broken tools (like Drills, Taps, Easy Outs), hopefully mobile. You've got big cities up there, somebody's got to be doing this.

If RV has do go to a shop, see if you can wrap the area in something that'll keep it from burning the area and drive it. If they can't come to you, and you can't drive it to them, disconnect the driveshaft and have it towed.

This thing has got me scared.

[tote]

If there is any stud sticking out this tool works amazing.
I broke off 3 bolts doing the water pump and this got out all 3 no problem. Worth it just to have around.

https://www.amazon.com/Shop-Iron-16023-Drive-Extractor/dp/B00265M8N4/ref=sr_1_1?ie=UTF8&qid=1503001759&sr=8-1&keywords=stud+removal+tool

[ron_dittmer]

Easy outs are for "Easy Out" conditions. Not "Rusted In" conditions. But you just now have learned that.

If there is enough stud remaining, do as I said before and grind or file opposing flat spots for a vise grip to grab good. A Dremel tool works well for that. Then with the stud red hot....do what I said earlier.

If the stud broke off flush.....good luck drilling out the hardened steel easy out tool.

[j-d]

Get thee to a shop with MDM disintegration equipment! Depending on where you are, there may be a mobile operation that can do it. That machine won't care if the pieces are hard like easy-out or a little softer like a stud.
This Linkgives you an idea how it works.

There's a welding-related tool called "Plasma Cutter" that might also work. Inquire at a good automotive machine shop.

[jcb47769]

Drilled it out a bit, got an easy out in there, heated it up, and snapped off the easy out in the bolt. Back to square 1

[ron_dittmer]

I would feel much better if I was able to remove the stud and reuse the threads. Grind two flats on it to get a good vise grip on it, heat the stud red hot with the vise grips off, then clamp down and swivel back and forth to work it loose. Red Hot, remember Red Hot, especially the back side you won't be clamping down on. You will be able to do it with a propane torch, especially because there is not much metal mass around it. Remember to use lots of layers of aluminum foil around it to protect the rest.

When I had initially mentioned manifold bolts, I was referring to the bolts that hold the manifold to the engine. Check them to make sure the bolt heads are not missing. Look for burnt & leaking gaskets. If all looks good, do NOT attempt to tighten the bolts. Leave well enough alone. You don't want to break one.

But it was surely a good thing you found this leak.