Rough idle on my 91

[skafifer]

Ok...so we got my wife's 91 (162k) put back together after a head gasket job and now we can't seem to get it running right...

It keeps throwing a code 71 (EGR System) and there is a rough idle once you've gotten it up to speed and brought it back down a couple of times (like the 2nd or so stop sign it starts to rumble, drop below 600, sometimes all the way down to 400).

here's a list of what's new:

• Fuel Pump w/ Fuel Sock
• Fuel Filter
• Head Gasket
• All Vacuum Lines
• Cap
• Rotor
• Plugs
• Wires
• Intake Hoses
• Rebuilt Power Steering Pump
• Power Steering High Pressure Line
• Low Pressure Return Lines
• EGR Valve
• EGR Modulator
• PCV Valve & Grommet
• Stock Height Replacement 1” Lift
• Front Bumper & Winch
• 31x1050x15 Goodyear Wrangler Duratrac Tires
• Alternator Belt
• AC Belt
• Water Pump Belt
• Radiator cap

Also, the radiator did have to come out and have the bottom spout fixed, and since we've put it back in there's a coolant issue now, too...it seems to be losing 1/4 gallon of coolant per every other driving session, but there's no leaks underneath it or on any hoses/tubes when parked...

I'm really at my wits end here...when my wife drives it to work she puts it in neutral or park at lights so that it won't idle as rough...I'm nervous to let her drive it because i don't want her to get stranded...

any thoughts as to the code 71?

any thoughts as to the rough idle?

any thoughts as to the magical disappearing coolant issue?

thanks all...

dan

i've posted this to the 3fe board too, but was wondering if people around here had any other suggestions as well...

 

[Michael Hanson]

Check to make sure you are not leaking at the valve cover and large corregated hose could have cracks.Did rad. get boiled out? MIke

 

[inkpot]

Howdy! Before I got down to the part about the missing coolant, I would have guessed that you got trash into the EGR passage during the rebuild. But, with the coolant dissapearing magically, I wold say it is going out in your exhaust. You may have a head gasket leak, or a crack in the water jacket somewhere. Pull your plugs to smell for coolant. Went thru similar problem on a Mazda pickup years ago. Even in our 112 heat, coolant does not evaporate very quickly. It sounds like it is being burned up and going out the tailpipe. HTH John

 

[skafifer]

Just came in from draining the milkshake....er....oil.....well,it was at least 1/2 oil....now its time to find out how its getting in there. I'm thinking its probably the oil cooler (well hoping at least as I just did the head gasket and don't want to have to do that again...)...but how do I check/what am I looming for? Thanks....Dan

 

[skafifer]

So the question now is....where all can water and oil mix? I'm thinking

1)cracked head
2)screwed up head gasket when we put it back together (when we torqued down the head bolts we did them all in the right order but did them straight through one at a time instead of all of them in stages)
or 3)oil cooler...how do I check/know if this is the problem?

If it is the head...I guess my options are

1)repair this head....cost?
2)buy a used one (which would still need to be checked out at a machine shop)....cost?
3)buy a reconditioned head ($515)

So...does anybody know of a good machine shop in the Phoenix area?

Thanks....Dan

 

[Tools R Us]

Ok...so we got my wife's 91 (162k) put back together after a head gasket job and now we can't seem to get it running right...
...

Why was the head job done in the first place, symptoms similar to now? How do the plugs look?

If the symptoms are similar, chances are that the original problem wasn't fixed? Before I tore it apart I would want as much info as possible, so I would have the highest possible chance of correctly repairing.

The water leak and miss are probably related, water getting into a combustion chamber. This can happen at the head gasket, head failure in the combustion chamber or intake port, cracked block high in a cylinder or in the intake, like a leak in the intake heat area.

The things that I would want to determine: What cylinder is missing? Is combustion gasses getting into the cooling system? If so it's likely a head gasket or combustion chamber crack. If not it's more likely to be an intake port crack or intake manifold problem.

 

[BoondockSaint03]

Hello, curious if you checked the head with a straight edge to see if it was warped? It can be warped quite a bit and still look fine to the naked eye. Sounds like it is warped.... which depending on how bad it is can be fixed by having a professional plane it. I had that happen to my 22RE in my 86 P/U. The guy that I had do my headwork is a master course he's in IL so that is no help to you. Good Luck

 

[skafifer]

Why was the head job done in the first place, symptoms similar to now?

the head job was done originally when i purchased the vehicle 2.5-3 months ago...i had test drove it twice over 2 separate days, different times of day, and it drove fine...driving it home it started running like poop...ended up being a tear in the head gasket between 1&2 (i was only getting like 30psi in those 2 cylinders)...

 

[inkpot]

I would start by pulling out the spark plugs to see if you can identify which cylinder is the bad boy. Should have an obvious smell of coolant, and probably some white snot on the plug. John

 

[skafifer]

3 seems to be the bad boy, but it wasn't white snot, it was as black and oily...




if you click on the picture you can go to imageshack to view the picture and zoom in closer...

dan

 

[skafifer]

Ran a cylinder compression test and got a bubbly radiator = bad HG...well we tore it apart but are stuck...literally...the danger head wont come up even using an engine hoist....any suggestions on what to do to break it loose?

Also...we found a machine shop...Morrison Auto on 54th Ave & Glendale. My buddy drove by their shop and saw a bunch of straight 6s sitting out front so we figured Wed have them take a look at it....anybody Ever use them?
Dan

 

[inkpot]

I would soak it all with PB Blaster or whatever, and put LITTLE lift on it with the hoist. Then, find a corner where you can get a cold chisel in a bit between head and block. Start tapping with a small hammer, like a 8-10 ball peen. Sometimes the shockwave works better than a 4 pound drill hammer just dukin' it out. John

 

[Tools R Us]

Ran a cylinder compression test and got a bubbly radiator = bad HG...well we tore it apart but are stuck...literally...the danger head wont come up even using an engine hoist....any suggestions on what to do to break it loose?
...

Make sure you have ALL fasteners out! Especially if freshly done it should not be stuck that tight.

 

[BoondockSaint03]

on the 4 cyl Toyota's there is a bolt on the very front of the head that screws down into the timing cover make sure if there is one there that you take it out. It's an easy one to miss.