Quad 4

[tgardone]

I have a 2.3L Quad 4 in my 1990 Grand Am. I have been experiencing some hesitation in the engine during high speeds in top gear, particularly going up hills. It seems almost like an ingition miss but I replaced the plugs and plug boots not long ago. I'm thinking it might be clogged injectors or maybe bad gas? I have run some injector cleaner and carb cleaner through it in the past and it seemed to help a little, but the problem is gradually returning. Also it seems to backfire just a little bit when I shut it off, just a little bit, not much. Any help or suggestions on this issue would be appreciated!

[FieroSpeeder]

I can suggest a few things to check.

Did you replace the fuel filter?? They are not that expensive to replace.
If you have a fuel pressure gauge, you can check the pressure.

Get a timing light and see if each plug wire emits a light. If one doesn't, you can have a bad module.

does your egr valve look dirty?

[tgardone]

yes I have replaced the fuel filter, that was the first thing I did before I replaced the plugs and plug boots. if it is the egr valve, where is it located on my car? and if it is dirty, can I clean it? what can I clean it with? or do I just have to replace it? any other suggestions on what could be causing the problem?

[wileys_farm]

could your converter be stopped up? Did you gap your plugs right? Maybe its you distributor cap or rotory button?

[16secGA]

I have a 1995 Pontiac Grand Am 2.3 liter DOHC also.

All I can say is...Awesome car!!!!

But for your problem....If it hesitates is it when your trans shifts gears? (Do you have auto or 5 speed?)

Did you also replace the OS/2 sensor?

the 2.3 is distributorless and has no wires. Just to let everyone know that is asking about the wires and distributor.

[tgardone]

I have been keeping an eye on what it does and when it does it. I know that it is not a hesitation when it shifts gears but it only seems to do it in 3rd and 4th. It seems to only do it when you are going faster than 45mph and up above 2500 rpm. It does idle just a little bit rough sometimes. Someone told me to check the EGR, but what the EGR does when it is bad aren't the symptoms that I have so I don't really think that is the problem, but hey, I'm no mechanic. Anyways, I tried running some good injector cleaner through it thought that might be the problem, and it did seem to help for a little while, but that is the only thing I have done so far. Also it seems to only do it like I said before in 3rd and 4th under power, like going up a hill, it also makes some popping sounds out the tailpipes. Going up hills is a pain. It seems like an ignition miss but like I said before I replaced all that. Could it be spark plugs or anything like that? I have no Idea what to do with this, don't really know if I wanna spend the money to take it to a mechanic, some of them charge an arm and a leg. It is really frustrating me and I need help! All help is appreciated.

[16secGA]

Okay,

They way you describe it, the problem could be a bad spark plug. When was the last time you replaced your plugs? I run Bosch +4 plugs in my car. A little on the expensive side? Yes! But well worth the dollar. I have had them since dec. 00 and still run them hard on the track and on the streets. You may want to try them instead. I am no mechanic either, but I have had experiences with Spark plugs to know that some of the brands on the market are very overrated. As I asked before, have you checked the O/S 2 sensor? I am noticing problems with mine lately. Its still the stock sensor in my car and its about 7yrs old now. I caught backfire on mine last night for the first time ever and am hoping it was the O/S 2 sensor because I noticed its going out on me also. That could also be the backfire problem with your car. Does it smell like someone has "passed gas" in your car when you turn it on, drive it up a hill, turn it off? I don't think oil will make the car hesitate in a higher gear, but have you checked or replaced oil? And one more question, Is your car a manual or automatic?
~Drive Safe~

[tgardone]

Well lets see, I replaced the spark plugs, plug boots and fuel filter all at the same time about a year ago, give or take, the problem with that one was much more severe than it is now, one cylinder wasn't firing at all. As for the OS2 sensor, I have only had the car for 2 years and haven't replaced it and have no records on the car that indicate that it has been replaced, so that could very well be a problem. What are the symptoms of a bad sensor? The kind of plugs I run in my car are AC Delco plugs, I was told that it is a good plug and was told by a friend of mine that plugs shouldn't go bad this early but maybe they will. The oil you are talking about is transmission oil right? Because the engine oil in in need of a change right now and I plan on doing that today. Again I have no idea about when the transmission oil and filter has been changed or anything like that. And it's an automatic tranny. As far as I know there is no smell or anything like that coming from anywhere in the car at any time when I drive it or shut it off, but I'll double check that the next time I drive it. I have been looking around on other websites including the Quad 4 website, and have heard about problems with the cover on the top of the engine arcing and causing a misfire, they say it was dealt with under recall for a while but was just wondering if you knew anything about that. Also I have seen that in high speed, high RPM situations a miss or hesitation could be caused by a weak ignition coil, just wondered if you knew anything about that also. Well I gotta wrap it up, the Steelers are coming on soon! Thanks for all your help.

[wileys_farm]

Get those AC plugs out of there. Go with the Bosh +4 like 16sec said. They are a true performance plug.

[16secGA]

Okay,

Not sure the O/S2 Sensor will help 100% but it may be time for that swap. Considering the age of the car. Have you ever had the timing belt done on the car? And if you have any auto you may want to consider changing AND Flushing out the tranny fluid while your at it you might as well do the engine oil at the same time! Definetly upgrade to the Bosch plugs From what I have heard is that they are the best plug currently available. I wanted to upgrade to the Denso Iradiums that SUPPOSABLY increase hp. But then I found that the Bosch out perfroms the Denso Iradium plugs!!! I know the Bosch does not Increase HP but I have noticed Higher Shift points with the +4 plugs. YES there was a recall on the 2.3 Grand Am starters. Mine was replaced at no cost this past Febuary. BUT this was also a problem with Trans Ams a few years back. I have a friend that was stationed in Germany and ordered a Trans Am because him and his wife loved american cars. Within the first week that they drove the car the starter caught fire and it craweled up the steering column. (NOT good GM). And being stationed in Germany my friend couldn't do anything about it except get pissed off and buy a BMW.
Backfireing sounds like a Catalytic converter problem also. You might want to have that checked. But definetly do this:
1) upgrade sparkplugs
2) flush engine and trans fluid

then see how the car handles.

Hope that helps any.
~drive safe~

[wileys_farm]

If the car idel's kinda rough and misses on top end it could be a burnt valve. Try a simple tune up and check your timing componets, if the problem still persists I would say burnt valve. Just remember start with the easiest thing first and narrow the problem down.


wiley

[16secGA]

If its a burned Valve the car would be producing smoke also.

[tgardone]

Well I guess there has been enough talk, time to take some action. I'm going to go pick up a set of bosch +4 plugs and see what that does. Might as well start with the simplest thing first, one thing at a time.
Let you know what happens

Tom

[16secGA]

After careful consideration, and the fact that you mentioned that you do not have previous maintainence records, you may want to consider an engine and trans rebuild. That may be the safest route to take.

[tgardone]

I think the safest route for me is to have a mechanic look at it, which I am having done in a few days. I don't think an engine and trans rebuild are in the cards right now for me, I just need to fix it so it runs right, not get a brand new car. Thanks for the suggestion but I think having a mechanic look at it will hopefully solve the problem, if that doesn't work then I just need it to last till maybe next summer then I want to trade it in and let someone else worry about it.

Tom

[ballistic1974]

i had a 93 olds acheva had the same problem took me 8 months to figure it out try replacing the crank position sensor its in the block right behind the starter motor this is what tells the computer when to fire the plugs if it gets dirty it wont send accurate info to the computer and cause a miss fire its only a 30 dollar part and a great place to start
good luck

[shlynsai]

quad 4? i have some solutions for you. 1st of all, wiley gives alot of great advices! he has help me out alot! it helped me!
2nd. hesitation over 45 mpr? sounds like my (LEMINA) oops, i mean lumina z-34 with a 3.4 dohc. i had the same problem too! what it turned out to be was the o2 sensor, & adjusting the mixture! they claimed that my car was running rich, & the sensor was no good! that costed me $260.00!!! 60.00 part, 200.00 labor!! try that! i have a haynes manual, & it doesn't say anything about the sensor! let me know if that is the problem. good luck! if you want to hear about nightmares about a 3.4 engine? ask me, & i'll tell you!
Aloha!!
Gene E
93 Lumina z-34 3.4 dohc (LEMON)!!

[tgardone]

thanks for the advice, the car has been running pretty good recently, I have put some real good injector cleaner in the gas. That seems to make the problems go away. But what i am wondering, is it just a temporary fix? I had a mechanic look at it, we drove it all around the town, and guess what? NOTHING, not a problem, ran perfect...lol. Isn't that always the way? I'll see if the injector cleaner worked after it all has gone through the gas and there isn't anymore of it in the gas.

Merry Christmas!
Tom

[tgardone]

if the o2 sensor was bad, wouldn't that trip an idiot light? what about the EGR, would that trip an idiot light too?

[tim]

were do you buy your gas from it sounds like you have got hold to
bad fuel go to the higher octane for a couple of fill ups to burn that bad stuff out

[Dylan]

In reference to earlier post, you made mention of Electric arcing of Voltage coming out of secondary coil packs into Ignition Coil Shell surrounding it...?

GM made their Coil Shells out of Carbon. Carbon is a very nice conductor of electricity. Shell looks black.

GM found this out and remade Shells with non-Carbon.White,non-conductive material.

I found this out recently when my car decided to die on the road for me one morning on the way to school.

I'm sure that everyone tries their best to fix the car of their dreams..LOL.. without spending too much money and of course going to a mechanic.

KISS Keep It Simple Stupid, I always like to remember that.

Take a look at all of your vacuum lines to see they are in need of replacement. You know cracks, dry&flaky, loose connections.
Do you have Cruise Control, and do you use it when you notice problems?

Also, for the idiot lights, You can unplug the O2 Sensor run the car at idle and see if an idiot light shows up on your dash. Wait for your car to get up to operating temperature. The O2 Sensor does not start working until it gets hot. As for your EGR, if it does not have wires running to it then you will not have an idiot light on the dash come on. If it is not electric then how will the computer monitor a fault.

[Dylan]

When I mean unplug the sensor, don't take it out of the Exhaust Manifold. Follow the one wire that comes off of it and where it connects to another wire disconnect it their.

[tgardone]

my coil shells are made of the white stuff and I don't think that is the problem. I haven't looked at the vacuum lines recently but they looked okay the last time I looked at them, when I was changing a starter, the second starter, ask me if you wanna hear a horror story about changing a sarter on a quad 4. I do have cruise control, but I hardly ever use it, the problems occur when I'm not using it. Thanks for the advice Tim, I never really thought about putting better gas in the car, maybe that is part, if not the whole problem, just using too low octane gas. I'll try it.

[Dylan]

I was just making mention of the coil shells.

Changing Octane levels on you your car will do nothing unless your engine is Pre-detonatining(igniting) before the piston reaches the top of the cylinder.

Octane ratings increase the Temperature at which fuel will ignite.
The higher the rating the higher the temperature it will take to ignite the fuel.

If your your running a high compression engine, or perhaps towing in the middle of Summer then you will need higher Octane.

As for gas you might have too much water in it or alcohol. It doesn't sound like Alcohol is the problem. The recommended amount of alcohol in fuel is 10%. Alcohol is used to absorb water.
Must be careful in Winter though. Fuel is usually pretreated with Alcohol and generally everbody goes out and puts Gas line Antifreeze in their cars. They never tell you that when buying your car:)

What is the horror story with the Starter. Inquiring minds want to know...

[tgardone]

Ah, the starter.
I don't know if anyone who sees this has ever changed a starter on a quad 4 before, but the starter is located at the front of the car underneath the intake manifold. To get the starter out you have to remove the manifold bracket that connects it to the block, the oil filter, the radiator fan, and the air filter assembly mainly so you can pull the starter up out once you get it off. Well, everything was going off without a hitch until we got to the oil filter, NO FILTER WRENCH, so we tried to stick a screwdriver through it and take it off but that didn't work, so finally after about fifteen minutes of screwing around, I finally cought an edge on the filter and was able to get it to screw off. Then we ended up going to buy a new filter and we found a filter wrench at my uncle's house on the way there....ugh. So the starter comes out and we get the new one in and everything goes good from there, and we finally start the car and it fires right up, no noises or grinding or anything, so that was good.
Then about 3 months later the starter started just clicking when you turned the key, not a lot, just every once in a while. Well I didn't think much of it, but when it started doing it more often and more often, then I started getting worried. It got to the point where it would click 5 times or more EVERY TIME, until finally one day in the garage I tried to start it and it clicked 10 times or more and I knew it wouldn't start so I got a new starter. That meant I got to do it ALL OVER AGAIN! Except this time we did it right. The starter was under warranty so it didn't cost me anything and my uncle owns an auto parts store so it wouldn't have cost me that much anyways.

there's the horror story, enjoy :)
P.S. I hope I don't ever have to replace a water pump...lol some of you probably know

[Dylan]

Lovely horror story!

Sounds like you had a lot of fun with the Starter.LOL

I dont know where the water pump is on your Quad4, but on mine its on the back, and you have take the exhaust manifold off and a few other things also.

It was fun...
It took me all weekend to do. It never happens the way it says in the book. Alwalys you run across complications.

Do you have condensation(water) problems in your crankase oil?

[tgardone]

The water pump on a quad is located in the same place, on the back of the engine, buried under the exhaust manifold, my mechanic told me that the dealerships were charging upwards of $400 for a water pump job on a quad, thats one of the reasons I don't want it to go bad.
Well my friend, nothing ever happens the way it is supposed to....lol, we're not Sam and Dave you know! lol

I don't think I have problems with condensation in my oil, but how would I tell?

what kind of car do you have?

[justen]

Sounds to me it's the timing thats off just a bit maybe retarded to much if runs rough sitting there. and then above 45 mph

[smart_cookie]

actually i just change the starter on an 90 grand am dual over head cam quad, and you dont need to remove all that stuff remove the oil filter and the air intake hose, then using a universal socked and an air rachet you can get the top bolt then using a long extention you can get the lower front bolt then slide the starter towards the front of the motor (crank pully side) and remove the wires then stand it on its end and it will just fit between the intake and the rad support.

[bbechtel16]

Replace both of your ignition coils. They are imfamous for going out on the Quad4. I just replaced mine tonight, fixed her right up. Though my problem was a little different. Mine would misfire at low rpms under load, but its probably still worth giving it a shot. www.gmpartsdirect.com With them being on top of the head, between the cam towers, and under a metal cover...they get quite hot, and heat kills eletronics.

Also: +4 Platinums are know to most of the Quad4 community to be complete trash. Do yourself a favor and get AC Delco RapidFire.

Your car DOES NOT HAVE AN EGR VALVE! When the Quad4 was in its hay day, it was efficient enough to pass emissions standards of the time w/o one.

[dougbfresh]

Do a compression and leakdown test FIRST-that will tell you if the basic engine is good. Then throw a vacuum guage on it. These are all basic test that will tell you if the engine itself is cool. I would then do a fuel pressure test. If the car has alot of miles on it, I would look at having the injectors cleaned if the other tests are OK. I found a guy that will flow test and clean (hydrosonically) them and flow test them again for 10-15$ an injector. The car is down since you need to send them to him but I did it on my Bonneville and the random misfire codes are all gone and I suspect your getting some type of misfire at high rpm's.