Intake Manifold Gasket R&R…

Intake Manifold Gasket…

This was the job I was dreading. When I first started working on what I thought were just a couple of minor unattended to maintenance problems, I’d tested for a bad gasket right off because a bad leaking gasket can also cause issues with idle. It had passed the test. Test was to spray carb cleaner around the intake areas on the engine with it idling. If the idle speed changes, either up or down, that means you have a leaking gasket. When I first did that test, it passed. No idle speed change. Then, after about a week of smooth driving after cleaning the throttle body, my Service [wrench icon] light came on. What now? I had purchased a OBDII reader with bluetooth and had installed the Torque app on my MotoX phone by now so I checked and I’m seeing a Plug #1 Misfire code. Reading up on that, I end up mistakenly replacing the two spark coils and the ICM (Ignition Control Module). The spark coils I pulled out were an inferior OEM model so they needed to be replaced anyway, but I could have saved money by sticking with the ICM since the old one is good. Well, no worries, I’ll just install the new one and save the old one just in case.

I had also checked the spark plugs…they’re fine…and the plug wires…also fine. Scratching my head, I spend hours searching online and my symptoms (flaky and inconsistent as they are) keep leading me back to a bad intake gasket. OK, I’ll test again. And sure enough, this time it fails the test. There’s a slight dip in RPM when I spray next to intake port #1. Not a job I wanted to do. Lots involved. People were saying it takes at least 3 & 1/2 hours. The cautions are numerous and include don’t lose the manifold bolts, there’s trouble removing the steering pump because of oddly positioned and different length bolts, several of the manifold bolts have to be removed from under the car, the belt is hard to get off and on, drain the radiator, etc., etc..

After reading all that stuff, I was about to give it to a shop when the weather got soooo nice to work on stuff outside, mostly cloudy, 70 degree weather. And I was staying near my brothers house with his garage, wide driveway, air tools, and his help. OK, I’ll do it. First off, I took it to a self-service car wash, covered the alternator with a plastic bag, and gave the engine a good washing.

Bought the gasket, and drove up to bro’s to work. Brought my Android tablet with me and watched this video while working: Manifold Gasket Video

That video was very helpful. Following along just made things very easy.

First thing is to mark position of and than remove the hood. With the hood gone, there’s more room in there to work, and with the improved light, you can see things better. Disconnected the battery negative.

OLYMPUS DIGITAL CAMERAAnd here’s few of the necessary tools that are needed. That ratchet in the middle is a special tool that when you rotate the red/black handle portion, it causes the ratcheting part to turn so you can loosen or tighten a nut without having to move the handle. Direction is settable like any rachet. The magnet tool turned out to be very handy…allowed removing all the bolts from the top of the engine. The offset end wrench helped too because some places it was the only tool that would reach the nuts.

OLYMPUS DIGITAL CAMERAAnd some other tools used.
OLYMPUS DIGITAL CAMERARemoved the plastic air cleaner shroud & tubing from the throttle body. OLYMPUS DIGITAL CAMERAKept track of all the bolts in ziplock bags that I marked with their function.OLYMPUS DIGITAL CAMERAAnd after I got all the manifold bolts out and pushed the manifold back towards the firewall, this coolant poured out. Perhaps a quart. I had forgotten to drain a couple quarts out of the radiator. That’s all you need take out. It’s DexCool so environmentally safe, or at least less harmful than the green stuff. OLYMPUS DIGITAL CAMERAPart of the job is disconnecting the fuel line from the throttle body, and the next picture shows a rag stuffed nearby the fuel line opening to help absorb the little bit of gas that spills out after it’s disconnected. This had actually been done before I’d moved the manifold. The instructions tell you to remove two bolts from the bracket that attaches and holds the fuel lines rigid. One bolt holding the bracket attaches to the engine block, and one bolt to the manifold/throttle body assembly. It looked to me like the OEM had machined a relief in the metal of the throttle body just to allow the intake assembly to be moved without getting any interference from that bracket. So I just removed the one bolt on the throttle body from the bracket, so the rest of the intake manifold assembly could move. Turns out that’s all that was needed. The other bolt holding the bracket to the engine block, wow, super difficult to get to. Not even sure I had the appropriate extensions to remove it. Glad I decided not to mess with it.OLYMPUS DIGITAL CAMERAPulling out these two rubberized & formed drain pieces shown in the picture below (one on the window above the passenger side windshield wiper, the other just under the drivers wiper) helped give room to move the manifold back closer to the firewall…which gave room to remove the old gasket and insert the new gasket.OLYMPUS DIGITAL CAMERAAfter pulling the old broken up brittle gasket pieces off, used carb cleaner spray on everything, than buffed everything with 500 grit sandpaper. Happy that the air intakes and water ports all looked good, no corrosion, pitting, scum, or anything. Installed the new Felpro ‘improved’ gasket. Pushed the manifold back in position and proceeded to get all the nuts back on the studs.

And this is the tricky method I used to avoid having to crawl under the car to remove or install those difficult to access manifold nuts. My hands are small enough that I could finger loosen or tighten most of them, that is after using a tool to get them started. And I could get a tool on all the nuts from the top, it’s just there was little room to work. And in some places, no room to move a tool back and forth with a ratchet like you’re use to when trying to remove or replace a nut.

I do have that special 3/8″ ratchet that if you ‘twist’ the handle (rather than ‘rotating’ the handle like a normal ratchet), it will rotate the socket, with selectable direction of movement. That was a big help with nearly every nut, along with extensions, and a deep socket of course. Nearly every bolt I was able to use that ratchet. Easy. The mechanic in the above video suggests using this type of ratchet and so do I.

Also, I used this strong magnet to actually walk the nuts off the last couple threads of the studs, or it helped start them back on after the new gasket was installed. Helped prevent dropping and losing any nuts and made things easier by far. It’s a telescoping shaft tool with a strong 1/4″ diameter magnet on the end. And with a regular screwdriver type handle. OLYMPUS DIGITAL CAMERAHere’s how it helped the most when removing a nut. After loosening the nut as far as possible using a tool of the several mentioned, and then my fingers the last 1/4″ or so, than I’d use the magnet to slowly rotate the nut until it walked off the end of stud threads, and then pulled it off the rest of the way using the magnet. Since it’s a magnet, no worry about dropping it, if you’re careful.

When it came time to return the nuts to the studs, here again, I would hold the nut with the magnet and slip it over the stud, then rotate it until it grabbed a stud thread or two. Then my fingers did the rest. After that, it was time to turn to a socket wrench, or ratcheting closed end wrench, or offset box end wrench for the rest of the threading. I was able to quickly and easily remove and replace all 9 bolts from the manifold using this method. From the top of the engine. No crawling underneath or going to the trouble of jacking it up onto jackstands. So much nicer, and cleaner, than having to jack the car up and crawl underneath. I’m stressing the usefulness of using both the special ratchet and the magnet tool because of all the advice I’ve seen in several places on the internet that always have you jack up the car and remove 3-4 of the manifold nuts from underneath.

There is a fly in the ointment though…if your bolts are rusted in place, and you really need a lot of torque to bust them loose, it may be necessary to use PB Blaster on them overnight, and a magnet tool may not be powerful enough to turn them onto or off the studs like I was able to do. My engine is very clean and mostly free of gunk, or rust, so I could finger set the nuts.


Since the nuts only need 22 ft-lbs torque, it didn’t take much on the final twist of the nut to get to that torque. Very little leverage was needed. According to the book, you start in the middle of the manifold tightening nuts and work outwards to the ends of the manifold. Taking three passes. I hope I got it all done right. Time will tell I guess. I couldn’t see how to get a torque wrench anywhere in there for that so I had to use best guesstimate. It’s only 22 ft-lbs so not much of a worry. I tried to tighten them as tight as I originally found them when I loosened them.

You might notice from the pictures that it’s getting dark. Started this job at noon, and it was nearing 5:30 pm so we’re losing daylight. But we were mostly puttering along, no hurry. Also we were watching an Oregon Ducks game so we took lots of breaks. I’d call it a 5 hour job, but most people say they did it in 1.5 to 3.5 hours.

On the passenger end of the engine, in order to remove the intake manifold, I’d initially had to remove the power steering pump. First thing to do to remove that, is put a long closed end wrench on the tensioner, and pull towards the front of the car. Or make, or buy a tool that does that. That relieves tension on the belt than you just slip it off the A/C compressor. Which gives slack on the steering pump, so you pull the belt off that pulley too. Make sure to make a drawing of the belt routing. We didn’t and it took us an hour to find the right way to put it back on later. In failing light as it was dusk around that time. Couldn’t find a diagram in any of the Saturn books or on the internet until later.

The pump has a long bolt at the 2 o’clock position than 3 same length but slightly shorter bolts at the 4, 8 and 10 o’clock positions. All accessed by turning the pumps flywheel to the right position and inserting a socket wrench into several of the available holes in the face of the pulley. Once the 4 bolts are out, you just push and pull the pump back out of the way towards the firewall. Here’s a pic with everything back in place later in the afternoon. The steering pump is left of center.OLYMPUS DIGITAL CAMERAAs I said, getting the belt back on right took us the most time as we neared the end of the job. That and checking and double checking everything was back in place correctly.OLYMPUS DIGITAL CAMERA

My brother finally figured out the belt routing by eyeballing and figuring. We got it into position, I pulled the tensioner with an extra long closed end wrench, while he slipped it on the A/C pulley. Whew. With the right tool shown in the video linked above, sure one guy can do that, but without it, two would be better.

Wasn’t until later that someone on pointed out to me that there is a label on the radiator that shows the belt routing…DOH!


Topped off the antifreeze, reconnected the battery, installed the hood, and started it up. Sounded great. Smooth like a fine Scotch. And the SES light went out, and has stayed out for the last 100 miles so far. A new best. Looking forward to having much better fuel economy.

After this job, I put a full tank of gas in it, and I’ve now used up around 1/4 tank. I can tell from expirience that my fuel mileage has jumped. It’s looking like I’ll be getting the 34 MPG this car is capable of getting, with A/C. That’s better than the 24 MPG I was averaging before.

So the job was definitely worth doing, giving an extra 10 MPG every time I drive so the 5 hours and $12 cost was worth the effort.

And there you have it. A backyard mechanic replaced a bad Intake Manifold Gasket on a Saturn SL1, saving at least $300, which is what I’ve read a shop would have charged.

Update: Dec. ’16 – Mileage has improved a great deal since the gasket was changed. It went from an average of 22 MPG up to 33 MPG.  With occasional A/C use. Not bad, worth the effort it took.