I've decided to amass all of my car's issues in this here thread. I've had my Z28 for less than a month and it's been nothing but trouble. Don't get me wrong, this car is everything I've ever wanted but it's proving to be a massive problem child. I just want a few different opinions before I go spending money I don't have on parts left and right. I'll start with the basics.

Car description:
1996 Camaro Z28
LT1 engine + T56 transmission
Bone stock
80,000 miles
One previous owner
Purchased at a small dealership
Was told by salesperson that the car had sat for an extended period of time, unsure whenLOW TRAC and ABS INOP:
Signs: Brakes are weak soon after start-up -- I'll make my way down the street to a stop sign while the pedal feels rock solid but the car fails to decelerate with a moderate amount of force. The LOW TRAC light comes on while this is happening and on occasion a clicking noise comes from the ABS module that sounds like coins falling into a slot machine. This continues for the next few stop signs until eventually the LOW TRAC light switches over to ABS INOP and the pedal becomes less firm. When this happens the brakes feel squishier, but the car can actually stop without a problem.Possible causes: There must be something faulty in the ABS system computer that is impeding my car's ability to stop right after start-up. I'm thinking the ABS unwittingly boots up with the rest of the car each time. Because it's malfunctioning, the car's computer doesn't see a correlation between pressure on the pedal and deceleration so it disables the ABS altogether after a few attempted slides past stop signs. What's defective and needs to be replaced? The salesperson did say the car sat for an extended period of time. Could this be a problem with the master cylinder itself? I've tried bleeding the brakes at each wheel along with the module itself with no luck.

Solved: The snap-in connectors for ABS speed sensors behind one of the front rotors had come loose. Just needed to be plugged back in.



Electrical issues:
Signs: I've had a few... Here's the extender version: https://camaroforums.com/forum/4th-g...bs-inop-61445/

1. Had the car in accessory mode while vacuuming the inside so I could listen to music and clean. When I finished, I went to move the car further up my driveway so I turned the key. As soon as it reached the standby position all power in the car disappeared, it wouldn't start and acted as if the battery was completely dead. I came back five minutes later and the car started right up.
2. Was driving through a very hilly town with inclines you'd expect from San Francisco streets. When one of the roads leveled out I looked down at the gauges and noticed that everything had gone haywire. After the radio cut and my headlights started flickering, the tachometer, speedometer, and a couple others were acting up by flying all over the place. The engine seemed to be fine at the time but instinct told me to immediately turn the car off and roll the car to a stop to prevent any damage. The everything went back to normal except the speedometer which was stuck up past 150 mph. I was then able to start my car back up again and move it into a parking spot without a problem except the malfunction speed gauge. Soon after, the car lost all power like it had before. I waited another five to ten minutes and was able to start the car up and drive it back to my house. The speedometer flung back into the correct place in the middle of driving.

Possible causes: These...

1. Bad alternator? (Seems unlikely; Alternator appears to be doing its job by keeping the battery at 12.71 volts while off, 14.13 volts engine on... possible hiccup? Even if the alternator did hiccup, wouldn't the car's systems continue on battery power?)
2. Bad grounds? Yet to check.
3. Bad battery cell? (Seems unlikely; Voltage is fine at 12.71 off and 14.13 on)
4. A short circuit? (Very unlikely; No problems with fuses to date)

P0400 Exhaust Gas Recirculation Flow:
SES light came on halfway home from the dealership after buying it. That's the last time I buy something "AS IS." I used a friend's OBD2 diagnostic tool and pulled up this code. Something must be wrong with my EGR system but I have a few questions before I go messing with it.

1. Would a stuck open EGR valve cause my car to run rich? The car's cabin reeks of gas and there's a distinctive pop/gurgling noise from the exhaust when I remove my foot from the throttle. My father, a former mechanic who left the field in the 80's, claims the car is running a bit rough. The car is a bit shaky at idle and makes it look like your hand is twitching while on the shift ****. Also, my gas mileage is GOD AWFUL. I'm talking 150 miles on a full tank of 15 gallons, a pitiful 10 mpg.
2. Are there any disadvantages mpg wise to removing the EGR? I might just delete the sucker.

I used shbox's test to see if the EGR valve itself is blocked. While pressing on the diaphragm and opening the valve the engine's rpm dipped slightly and began to run rough. At least I know the valve isn't clogged.

 

unhook the battery and clean your battery terminals and the wire ends. wire brush the heck outa them while your at it clean the wire ends on the wires to the power junction box. (small red plastic box on the passenger side fenderwell) theres a ground juction there to, cleam em. there are a few grounds to the motor. one on the front diver side below the coil. one on the front passenger side under the tensioner, one on the passenger side motor mount and one on the passenger side of the block in front of the starter. theres a sticky by massey on the body control modual, you might want to read that and see if it helps. a failing speed sensor can cause issues with the abs, you may want to check over the wires to all the wheel sensors.

 

1. Take it to an autopart store, most can test them on or off car.
2. Listen to what I said in the other post and what crabby said here. Check them good.
3. Bad Cells can cause all sorts of strange things to happen. Just trust me here. Have the battery tested, again local autopart stores are your friend.
4. Does your battery drain over night? Do you smell burning wires? Are you always replacing the same fuse? if no then you prolly do not have a "short" a short will usually cause bad things to happen pretty quick and you will know when a short happens. Usually a bad ground is mistaken for a short.

With the ABS and low trak issue, are you getting a speed sensor code at all? Does your friends OBDII reader read the ABS system codes? Get that checked out soon as you can. Most autopart stores done spend the money on the scanners that can read ABS codes.

EGR will cause a rough idle, it will not cause the gas smell or the loss of mileage. EGR actually helps your cruising mileage so it is a good idea to leave it alone. Older EGR systems were junk but the new systems actually help the engine. The gas smell could be bad injector seals and that would also explain the poor mileage. You should get mid 20's on the freeway and mid teens in town if you drive it nice. 10MPG if you are always putting your foot into it.

If you dont know when the last tune up was, do one. The cap and rotor are hell expensive for the LT1 but I know a trick that will save you a few pennies and make that the last cap and rotor you ever pay for. Buy this:
Richporter Technology GM05 - Distributor | O'Reilly Auto Parts
It is a new lifetime warranty dizzy that will cost less than the BWD cap and rotor. Did I mention LIFETIME warranty? Yea so even if the water pump tanks the opti you are still covered. When it comes time to replace the cap and rotor just take the whole unit off the car and bring it back (it only takes 3 more bolts to remove than the cap and rotor do) and get a new one for free. Neet trick huh? It would also be a good idea to get a new water pump at this time too. Get the new not the remanned here (again just trust me).

Your plugs were Iridium from the factory I would recomend putting them back in. Yes I know they are $6 or $7 per, but they are worth the extra coin. New wires also are a good idea.

Massey

 

ABS -- I'm going to check the ABS speed sensors later today but I'm not sure of the exact locations. I've been told that there are 2 up front behind the rotors and 1 on the back near the trans (I might be thinking of the wrong one)?

Electrical issues -- The battery seems to be doing its job and I'm not sure how it would affect the car's systems beyond start-up. The car has always started without a problem (excluding the 2 incidents going from accessory and while driving) and my multimeter reading appeared to be normal (12.71 volts off, 14.13 volts running). Battery doesn't drain overnight and the alternator appears to be doing its job. The car probably isn't shorting because I haven't had any trouble with my fuses. I guess this leaves the ground issue but I'm unsure of how a ground issue would affect the car randomly (my 2 incidents) rather than just on start-up.

EGR Flow -- I ran the Shbox test to see if my valve is functioning properly. When pressing on the diaphragm and opening the valve the car starts to run rough and the revs decrease slightly during idle. At least I know the EGR valve itself is working. Could there be a vac leak somewhere? How exactly does the DTC P0400 Exhaust Gas Recirculation relate to my car running rich?

 

i have had my daughter call me up and tell me her battery is shot and she needed a jump. i asked how she knew the battery is shot and she responded, its done it a couple of times and when they jump it it works fine, starting and all. i asked if the terminals have been cleaned and she tells me how they looked at them and they are clean. so i tell her ill be right there. i show up and clean the battery terminals with my knife (no wire brush on hand) and wire ends and it starts right up without a jump. now this may or may not be your issue but its free and easy.

 

I touched up the terminals a bit but I don't think they're the source of any problem. On the few times I've had trouble starting, I'd give the car a cool-down period of about 5+ minutes and then it will work without a problem. It still doesn't explain why the electronic components of the car went haywire mid-drive being that the alternator should power the car completely even with a hiccup from the battery. I doubt that the alternator is bad because it's kept my battery voltage spot on demonstrated by the multimeter readings.

Also, I think I solved my ABS INOP problem by checking the connectors for the speed sensors on each front wheel. It felt as if the driver's side one had come loose and just need to be replugged.

 

almost all the sensors/gages are ground activated so if you have a lose or bad ground it can really mess things up. there are also a couple of grounds inside the car that should be checked. g200 and g201

 

I'll go through all of those grounds tomorrow...

On an unrelated note, could there be an issue with the AIR valves causing my car to run rich? My father seems to believe they're the root of all my problems and it's a $30 solution. I'm just wondering how that connects to the P0400 DTC. I'm pretty sure AIR DTCs start up at P0410+...

 

Grounds look alright, haven't had an electrical problem with my car since. Still can't find the root of this EGR problem.

 

My car just spat out another P0400

Fuel Sys 1 -- CL
Fuel Sys 2 -- CL
Calc Load % -- 10.9
ECT (Fahrenheit) -- 188
STFT B1 -- -0.7
LTFT B1 -- 11.7
STFT B2 -- -0.7
LTFT B2 -- 10.9
MAP (in Hg) -- 13.5
RPM -- 1691
Speed -- 36 mph
TPS % -- 13.7

This look normal? I'm unsure what the STFT and LTFT mean, but I know LTFT's look a bit high (I'm guessing rich?)