Can't seem to fix this car?!?

[truck1985]

I have a 2004 Saturn Ion 3 with the 2.2L Ecotec and 5 Speed Manual Transmission. About 2-3 months ago, I very abruptly started getting a lot of noise from the engine. About two days later, a gouge appeared in the valve cover. Upon further investigation, I found that two of my timing chain guide had catastrophically failed. I changed out the entire timing kit, valve cover, and dropped the oil pan and cleaned it. Since then, the problems seem to keep coming. My IAC (idle air controller) went bad (I have replaced it). I started getting a p0172 DTC (system too rich) and P0107 (MAP/Barometric Pressure Sensor). I have removed the Catalytic Converter to make sure it wasn't clogged (didn't fix the problem so I reinstalled it). I have changed the oil several times. I have replaced the spark plugs twice. I have replaced both my upstream and downstream O2 sensors. I have replaced the MAP Sensor twice. I am still getting the engine error codes, even after all of this. I ran a fuel pressure test. I got good results from that, except when the engine is idling, the pressure is all over the place when I am idling. The engine does idle a little rough. My research elsewhere has told me to replace the Fuel Pressure Regulator (my local GM dealership tells me there isn't one on the '04 Ion). I am at my wits end, and am tired of throwing parts at the vehicle. Does anyone have any suggestions? I don't want to take it to a shop if I don't have to--please help?!?

[Maritime Storm]

Are you sitting down? Hook a vacuum guage up to the engine on the intake ports(they are 2) while it's idling, if the reading is low(and I suspect it is), chances are you are pulling the timing cover again to see which cam is out of timing.

[2006 ion2]

or if you have access to a proper scanner, or have any way of reading MAP, you can use that. I have my MAP and many other parameters available on my scangauge 2

[ssicarman]

Welcome to the Board.

The fuel pressure regulator is as far as I know is part of the fuel filter.

As Maritime Storm said recheck the crank to cam timing. If none of this was happening before replacing the chain then it would certasinly point to a problem there.

[Maritime Storm]

Yep, just like the last generation S-Series, the regualtor is part of the fuel filter.

[truck1985]

The Fuel Filter has been replaced, so I guess that means the problem isn't there. I do have a quality code scanner. It gives a MAP sensor reading of about 16-17 inches of mercury. I know that that reading should be around 12 inches of mercury, though I don't know if that tells you anything. As far as the vacuum gauge test, I just got a vacuum gauge, and will be using it tomorrow, time permitting. Hopefully I don't have to tear the engine down again, that would really tick me off. Thank you for your advice/input, I appreciate it.

[2006 ion2]

sounds like you have a vacuum leak if your vacuum is higher than normal (map has too many variables to be truly universal). check your brake booster hose, TB to intake manifold gasket, and intake manifold to head gaskets. if you are still getting high MAP and they look good, replace them.

[ssicarman]

Originally Posted by truck1985

The Fuel Filter has been replaced, so I guess that means the problem isn't there. I do have a quality code scanner. It gives a MAP sensor reading of about 16-17 inches of mercury. I know that that reading should be around 12 inches of mercury, though I don't know if that tells you anything. As far as the vacuum gauge test, I just got a vacuum gauge, and will be using it tomorrow, time permitting. Hopefully I don't have to tear the engine down again, that would really tick me off. Thank you for your advice/input, I appreciate it.

If you are actually getting a correct reading of 16-17 inches of vacuum then that is a good number. Engine vacuum will vary to a degree on the altitude of where you are, the higher the elevation the lower the vacuum that can be gotten. Your reading is decent. 12 inches would be low at most normal elevations.

Reread your fisrt post.
You say that the fuel pressure readings are all over the place. They certainly should not be. If you got an aftermarket fuel filter it may be worth while getting an OEM one to see if the pressure readings steady out.
You said that you got good pressure results other than at idle. What is the pressure that you are getting that you say is good?

[truck1985]

2006 ion2, I am not entirely sure what these items you are talking about are. ssicarman, the fuel filter I installed is OEM (from the dealership). My idle fuel pressure is between 40-70 psi, but when I did the pressure test with the key on, engine off, the pressure was steady at about 55 psi, which is mid-range for that test. As for my MAP reading; I am at sea level...I don't know if that tells you anything, but according to alldata, it should be around 12 inches, being at sea level, when idling. I am not sure how to check that I am getting a correct reading from my MAP. I am getting the reading from my Actron Code Scanner, so I can only hope that it is correct. I still have not been able to run my test with the vacuum gauge. I am hoping to do that today, though I am not entirely sure how, hopefully I can figure it out once I actually open the package for the tester.

[2006 ion2]

the brake booster hose that gives your brake booster vacuum assist, the gaskets are the ones between your throttle body and engine. if you do not know these terms, I think you should take your car to a dealership and let them fix it.

[Maritime Storm]

Your MAP sensor is telling you it's reading 16-17 inch of Mercury, does a hand gauge confirm it? If so, move on to having the injectors cleaned, sounds like one may be sticking open intermittently(have run into this in the past), your fuel pressure off is within specs, but shouldn't be varying that much when idling. If you haven't hooked a hand held gauge on to the vacuum ports on the intake, do so to rule out a bad MAP.

[truck1985]

Originally Posted by Maritime Storm

Your MAP sensor is telling you it's reading 16-17 inch of Mercury, does a hand gauge confirm it? If so, move on to having the injectors cleaned, sounds like one may be sticking open intermittently(have run into this in the past), your fuel pressure off is within specs, but shouldn't be varying that much when idling. If you haven't hooked a hand held gauge on to the vacuum ports on the intake, do so to rule out a bad MAP.

Did the vacuum test, and here are the results: Needle fluctuates between 12-15 inches. Haynes manual says that it should be steady between 17-22 inches. The Haynes Manual says to suspect an intake manifold gasket leak at an intake port or a faulty fuel injector. Does anyone know a way to test fuel injectors without one-by-one replacement (since that gets expensive)?

[2006 ion2]

a bad injector would most likely throw a code to that effect. suspect your gaskets (TB to IM and IM to head) and brake vacuum assist hose.

[2006 ion2]

sorry, just realized your MAP is LOW, not high. if it's low, you might have a much larger issue. not sure what besides improper operation of the engine or improper throttle plate position would cause this.

[ssicarman]

Link to an old school vacuum gauge diagnostic chart.

http://www.classictruckshop.com/club...ts/vac/uum.htm

[truck1985]

The wife and I finally got tired of putting so much time, money, and effort into fixing this vehicle ourselves, so we took it to a shop. They want to replace the IAC, the MAP, and the catalytic converter. I am allowing them to replace the IAC and MAP, but am opting to replace the Cat. myself, because they want to charge me $700 for the part alone, and I can get it for $330. I do have a question though; they want to remove my throttle body and intake manifold to clean it. They say the cost is $200, most of it labor. Is this job something I should allow them to do, or are they just trying to get some extra money out of me?!?

[2006 ion2]

for how to clean the TB, http://www.saturnfans.com/forums/sho...53#post1640253

but you will have to get creative to clean the manifold, it's kinda twistie. as far as the cat goes, you cannot just replace the cat on these cars, the cat is integral to the downpipe, so you replace the downpipe to replace the cat, no exceptions.

[truck1985]

The shop finally got my parts. They replaced the IAC and the MAP. The system too rich code didn't go away. I replaced the cat, and had no problems doing so. The system is still running rich, and I am at my wits end trying to figure out what to do. The shop that I took the car to wants $1000 to open the engine, and reset the timing, but they won't guarantee that will fix the car. Any suggestions on what my next step should be?

[fdryer]

Other than observing the fuel pressure fluctuate, injector leaks are probably hard to check other than pulling the fuel rail out along with the injectors to lay out in the open and connected with ignition turned on; as soon as the fuel pump cycles (2-3 seconds), pressure will be at the injectors and shouldn't leak at all. Any leak from any injector will be obvious. In the engine with the ignition ON the injectors just sit still until the engine cranks over. The cps generating timing signals turns on the ecm and the ecm starts the EFI system; turns on the fuel pump, initiates the ignition system, and pulses the injectors. No engine turning over = no injector pulses. There should be no fuel coming out any injector valve.

[truck1985]

I have already run this test, and there is no fuel leakage from any of my injectors. They are holding preassure just fine.