Fuel Injectors

[ATF_Syris]

i have a 91 grand prix SE and in need of all 6 fuel injectors. The problem here is that im told they wont be cheap. My question for you guys is would you happen to know anywhere that might sell these sumwhat cheap? Or know sumone with a 91 grand prix that they are gettin rid of it.

[mdzcpa]

I'd look for a good junkyard. I'm sure they would have some off recent wrecks/junks.

If you can't find em used, just go with aftermarket (eg bosch), and skip getting the more expensive ac/delco parts.

[Player0]

You can do a lot to save fuel injectors. You can soak them in solevent, use a toothbrush to scrub them where you can. Are they really that bad? You might be able to get away with replacing just a couple of them

(saw this recently on weekend mechanic, he saved 2/3rds of them).

[ATF_Syris]

well im still driving the car.... But if i drive under 2000rpm the whole car shakes but when i jump the rpm's up the car stops shaking. A mechanic told me that the injectors need replaced

[Synthohol]

sounds more like the EGR valve is sticking...

[ATF_Syris]

im not too car savvy so could tell me a little more about an EGR valve sticking?

[Synthohol]

where fresh air is introduced into the plenum there is an electrical valve that adjusts the fuel to air ratio kinda, it lets the plenum suck in exhaust gasses for better fuel burning when the engine is cold. if it is stuck open (the pintle) it will cause too much exhaust gas to be let in at idle and will make the car stall or run sluggish until about 3000rpm when it wont make too much difference.
its usually bolted on by 2 10mm bolts and a paper type gasket.
which engine do you have? 2.8 or 3.1?

[ATF_Syris]

3.1

[Synthohol]

how many miles on it? a worn timing chain tensioner can cause it too, and they are a beeyatch on those engines to replave.

if you find your ALDL connector, shorting pins a and b not only flashes any codes on the ck engine lite you may need to decipher, i would start there. if the engine stalls it may be the chain tensioner:(.

[ATF_Syris]

it has 216,000 but it has been rebuilt around 100k ago.

[spldart]

Hrm. The wifes Cavalier shakes at idle as well. Never stalls though. And pulls hard if you romp it from idle on up to shift point. It's got the large 4 banger. I think it's an RS as well.
I can tell all cylinders hit while driving and it doesn't sound like it's missing when it's idling from the outside. Just the shaking.
Oh...And sometimes the motor will surge just a bit at idle. Feels like someone pushed the gas a bit. It only lasts a second or two the returns to idle. Happens once a day or less. Usually shortly after you start driving in the morning...
Sound like the same problem?

[Synthohol]

surging in a small GM is *USUALLY* an O2 sensor on its way out:)

[Player0]

Wouldnt that make the Check Engine light go on?

[Synthohol]

the O2 sensor will only make the idiot light come on every 60,000 miles to warn of the need to replace, otherwise it only sends info back to the ECM to enrich or lean out the mixture:)

[spldart]

Hrm....Where would I find the O2 sensor?

[Player0]

Next to the O1 sensor :)

On the exhaust manifold, helplessly rusted ;)

[spldart]

mmmmMMMMMMMmmmmmmm WD40 and a torch time :eek:

[ATF_Syris]

yea it does sound sumwhat same. Cuz like u can be driving down the road and ur whole seat will start rumbling like ur goin a bad country road or sumthin

[Synthohol]

other than PBBlaster a hot engine and a can of air will do it.
when the manifold is hot hold can of air upside down and freeze the sensor at the nut which will cause it to contract and should be looser then.
WaRnInG....all O2 sensors will want to strip on the way out...i dont know why they just do. crack'em loose and work it back and forth (tighten-loosten) a little at a time until it is completely out.
good news is that MOST 02's only have 2 or 3 threads and will work even stripped back in the manifold as long as the exhaust wont leak you will be ok:)

a simple test to see if the sensor is working is to unplug it and touch the wire leading back to the ECM and ground youself to the car, dont worry its only milivolts and see if the idle changes, you may have to wet you fingers first, and no i'm not kidding.
if yours is the 3 wire type only use the black wire as the other two are 12v for the built-in heater in the sensor.

[Synthohol]

Originally posted by ATF_Syris
yea it does sound sumwhat same. Cuz like u can be driving down the road and ur whole seat will start rumbling like ur goin a bad country road or sumthin Um, that usually means you have hit a raccoon:eek:

[spldart]

Well..I've procrastinated long enough...The car is now missing cylinders often and is weak off the line. I'm picking up an O2 sensor today. I have good plugs and air filter along with fresh fluids...Are there any other good tune-up items that should be replaced on a 2.2 chevy? EGR? Other sensors?
Thanks

[Synthohol]

new ignition wires for sure ;)

[spldart]

Guy at the auto parts store mentioned the possiblity of clogged up EGR passages :confused: Likey?
Hrm
I'll post later of my results ;)

[spldart]

Oxygen sensor has returned the car to better than we got it condition says the wife after she took it for a test spin. Sensor was 24.95
I have to admit I cheated and used a 7/8 box wrench to do the job. Old one didn't resist coming out much.

Thanks Synth.

[Kabooka]

Thats one advantage of living here in Houston.... The metal parts on autos don't fuse themselves together via rust... when I lived in Wisconsin I was replacing exhaust systems once every 2 years or so and I was always pissed at the rust under the car it was so bad I invested in an oxy acetelyne torch ... been in California for 10 years and here in Texas for 5 - and I haven't bought an exhaust part since....

Originally posted by spldart
I have to admit I cheated and used a 7/8 box wrench to do the job. Old one didn't resist coming out much.

Thanks Synth.

[spldart]

Ok. Bad news Synth. After several small trips this morning with the car driving beautifully the wife says it all of a sudden started doing the missing sputtering crap again. Are there any other sensors I should be worried about. Is there a throttle position sensor maybe?
I just dunno computer cars :(

[spldart]

Originally posted by Kabooka
Thats one advantage of living here in Houston.... The metal parts on autos don't fuse themselves together via rust... when I lived in Wisconsin I was replacing exhaust systems once every 2 years or so and I was always pissed at the rust under the car it was so bad I invested in an oxy acetelyne torch ... been in California for 10 years and here in Texas for 5 - and I haven't bought an exhaust part since....

I wonder sometimes if the salt they layed on the streets in Wichita when it iced did more damage on the cars than the salt air here in Corpus Christi or H-town.

:O

[tripodal]

I would look at the work you just did (make sure your wiring did not come loose) before you conitinue on replacing anything else. Bar that, you can use a Ohm-meter to test TPS. Does your care have an electronic IAC (idle air control, which could stick)

and of coarse you should check to make sure the EGR is working properly.

[spldart]

Should I be able to just take the car to a shop and have them read the codes for me? I wonder how much that would cost :confused:

[tripodal]

autozone advertises they will do it for free (on limited models)

I highly reccomend you buy a haynes or, even better yet, a chevrolet service manual.

[spldart]

Already have the service manual :)

[Synthohol]

under the dash there is an ALDL diagnostic connector, if you jump the a and b pins the check engine light will flash a series of codes like morse code, it will flash each code three times and i can read them from there.
only turn the key on do not start it:)
it will flash say 3 quick, pause, 3 quick then repeat it 3 times that would be a 33 code which is a bad map sensor...let me know:)

[Synthohol]

a 13 code is an open O2 circuit 21,22 bad throttle position sensor, 32, an egr problem and so on...

so count your flashes, they will be in a 2 digit code lemme know:)

the a and b pins are on the top right, the way you can tell is on the plastic connector, there is a keyway on the top center and two on either end of the bottom i will try to draw a pic:)

[Synthohol]

here ya go...

[spldart]

THANKS FOR THE WAY TO READ THE CODES! :D

I did the map and throttle sensors the hard way. I did a measurement with a dmm right at the sensors. Throttle position sensor varies from .54 closed to 4.6 wot. Book says .5 to 5 is normal so I'm thinking that is close enough. The map sensor gives blurps from a fraction of a volt to a couple of volts if you blip the throttle so information is being sent.
Main symptom right now is hesitation/missing.

[spldart]

blink.....blink blink...........blink.....blink blink...........blink......blink blink
blink.....blink blink...........blink.....blink blink...........blink......blink blink
blink.....blink blink...........blink.....blink blink...........blink......blink blink
blink.....blink blink...........blink.....blink blink...........blink......blink blink
blink.....blink blink...........blink.....blink blink...........blink......blink blink


I think it has a problem with 12 :confused:

[tripodal]

12 is either no error or bad ecu (on a honda)

[spldart]

12 is not a legitimate code according to the service manual I have for the car :( :mad:
Not even the car will tell me what's wrong with it :(

[spldart]

Closest thing I can find is 12 is the code for diagnostic mode. But I waited through 5 repeats of 3 of 12 :( Maybe there are no codes saved :confused:

[spldart]

Just did it again. 8 repeats of 3 of the code 12 :(

[tripodal]

try googleing it

[spldart]

Google is where I found 12 is the code for diagnostic mode. The service manual doesn't list anything smaller than 13.

This car is making feel stabby :mad:

[tripodal]

that means there is no code
Did you double check everything you did?
Your transmission could also cause a hesitation. (if the torque converter doesnt engage / disengage properly)

[spldart]

Nah. The tranny feels and shifts fine. I can actually feel the motor stumbling and hesitating. It'll even do it in neutral. You can stab the gas pedal and you get a hesitation sputter then the rev.

[spldart]

Oh...And I double checked everything I did ;)

[Synthohol]

yup, all is well. at least with the electronics, now we look at physical items, cat converter, bad timing/belt, trans etc...
i would look at the converter first, or bang on the ecu when it is hesitating, if it idles better its the whole ecu is porked they are less than 200 rebuilt

[tripodal]

Hrm, Air Filter, Fuel Filter are both good right?
Could it be bad gas? Occasionaly you can carry over a bad mix of gas when the weather changes very rapidly / extremely.

[spldart]

Well. As I said I can get it to hesitate in neutral and in gear the tranny acts like new so I'm assuming that eliminates that.
I assume fuel filter and catylitic converter tend to get clogged but I don't know how that would explain the still awesome WOT operation :confused:
This thing has been very slowly degrading over a matter of months and It fills up at the same gas station all my other vehicles and some of my neighbors fill up and none other have developed this kind of problem so I think that rules out gas.
How do I rule out timing belt? Or is there no easy way :(
Oh...And I'll try tapping the ecu :/

[spldart]

eeuww. Timing belt is a bit of work :(

[tripodal]

Timing belts always are, but if you have time and motovation, its not "difficult". RTFM :)
Timing belts also, cant really be judged for wear. All you can look for is to see if it has jumped. If you dont know when the timing belt was replaced last it wouldnt hurt to change it regardless of it causing your problem or not.

A faulty coil could cause that problem... low voltage from battery or alternator as well (increasing rpm would increase alternator output) if your battery is 1/2 dead.

[tripodal]

Your cap rotor or coil could be faulty. Or your timing could be off....
thats a good one.. check the timing.