Chevy8588

iTrader: (1)

well unfortunately they charged another hour of labor because in order to drop your tank that exhasut needs to come out, so now they have to either cut and reweld it, or they have to get another teh to help lower the system as a whole and risk snapping flange bolts, what do you expect? you change your car away from stock it makes other things take more time, most dealers would have charged an extra hour of labor to remove it cuz your wasteing their time and the tech's time otherwise. most of the time they will take the shocks and panhard and crosslink off your diff and let it hang by the trailing arms, that make the exhaust still hard to remove without the stock flange in place, see the reasoning behind that? if you were a tech and your time is your money, not being paid hourly, you'd be pissed too if you didnt get paid to work around it (- Ex GM tech)

Dealers arent always dishonest, in fact most arent, it just seems like the service advisors dont explain things well enough

as for your engine, let me guess, loose drain plug? not enough oil? wrong oil? soemthing like that?

Syclone Rob

Dealerships=Stealership... They didn't earn that rep by accident.... /end thread.

I would bet that you have a short in the wiring to the maf

Chevy8588

iTrader: (1)

lawl, well arent you the vocal one, im not here to start fights but do know this, you can either pay 95.00 a book hour to have your car worked on by a GM tech, and have the assurance that if something breaks they'll fix it, or go to a merlin's or meineke who hires anyone off the street with a craftsman 140 pc tool set and have that guy work on your car for 65.00 a book hour, your choice, btu when you get into a major accident cuz the uneducated bastard left your lug nuts loose, its all on you! you get what you pay for!

also, end thread? the op's problem has not been solved, who are you to walk in and say that? lol
im just sharing my side being one who worked for a dealership and hated hearing people complain about it when somthing cost more than they wanted, you should hear how many people thanked us personally for fixing what car ex charged 600 bucks and 3 days to make worse!

y84pauloflondon

Kinda, they replaced a intake gasket and allowed coolent to get inside the block. Not a big deal, a oil change Should be part of the repair anyway. they did NOT change the oil 200 km later, spun bearings!!!!

TO: OP sorry for getting off topic! Lets remember why we're here for....

Chevy8588

iTrader: (1)

awe man, im sorry to hear that one, you should ALWAYS clean the valley and replace the oil after an intake change, thats the result of a bad tech, not the dealership, i guarantee you he got a union write up, if not termination for that one. GM doesnt take kindly to **** like that, ESPECIALLY now

y84pauloflondon

Well thankx anyway, but they did not fess up to there mistake even though the oil was milky with silver flakes, and I was advised to buy a short block......3 Year/60 000 km warn. Rebuild 1 yr/ 20000 warn. I went short block, kept my org block.

Chevy8588

iTrader: (1)

wow, thats bull crap, please tell me you filed a complaint with GM over it?

y84pauloflondon

No, this was like 7 years ago and I was 22 yrs old. I don't think they took me seriously as a loving car owner...just a punk! (Maybe)......

Hey at least I put Maybe.....lol

Chevy8588

iTrader: (1)

lol, yea probably didnt wanna eat the job

y84pauloflondon

Anyway, lets see if this MAF will help them out tomorrow. I still think WileECoyote should try the disconnect when his car wont start. 2-3 days its run fine then the next it wont start!!! Could be a MAF on its way out, or pig-tail that plug in to the MAF sensor is loose or the wires are corroded.

What do you think of that Chevy8588? Could that be it?

y84pauloflondon

Well, who would?!?!

Chevy8588

iTrader: (1)

doubtfull, i dont think its a maf problem at all, even if the maf were bad it should stil set a mil and start the car, a maf either works or it doesnt, no in between, a bad maf with screw up the fuel trims, not shut off injectors, so the ECm either thinks its not turning, or the ECm is bad, or bad injectors shorting the ECM driver. not MAF related

y84pauloflondon

MAF #2, is some how NOT the right one....The dealer called this morning said it was running, no codes!!! Great right, nope, I get there, pay for it(dia & RnR), go to start it up.......Ran for 2-3 seconds and died.

Well its on too #3 from a diff reman company, A1cardone.....something something. I Hope Too God THIS One Works.

The first two were from Blue Streak. Dealer said that they are not calibrated right, they are read out 4gm's/sec and that they should be reading out 26 or so gm's/sec

Chevy8588

iTrader: (1)

the 85 one needs a piggy back controller, and V6 MAF sensors will not work, i could see a Reman being miscalibrated though

y84pauloflondon

The other thing too is, 86' and 87' MAF's were basically cali'd one way and the 88'-90' were cali'd aonther way. SAME MAF body, but with two different calibrations!

Am I right or wrong?

Chevy8588

iTrader: (1)

havnt heard that one yet

y84pauloflondon

So I was wrong then I guess. But the 86-87 MAF sensor is one part # and the 88-90 is another #. There body's are the same, but the guts are not.

Anyway, who cares! Lets see what happens tomorrow!!!

y84pauloflondon

#3 MAF is also no good....now its got code 34, but its running...kinda!

Chevy8588

iTrader: (1)

sounds to me like a short in the MAF circuit, or you have been VERY unlucky with your MAF's

33 MAF sensor indicated an air flow of 45 gm/sec or more for 1 second when TPS was less than 1/4 throttle and engine speed was under 2000 RPM. 34 MAF sensor indicated an air flow of 25 gm/sec or less for 1 second when TPS was above 6% and engine speed was above 2300 RPM.

y84pauloflondon

O.K. so I get a call of the dealer yesterday saying that the 3rd MAF was working fine, no codes and IS running, they just needed to keep it over night to put everything back together. They also took a look at my ECM and all the connections, said they look good aswell.

Today I get a call, "its done and runnig but it has code 34, give it a shot. And let us know." - O.K. So this MAF from A1cardone isn't 100% either!!!(According to them)-fine.

INVOICE: ***Tech Comments: Test for inputs and outputs for MAF sensors - to spec, tested for pcm knock test - did not respond (has aftermarket pcm). Inspected thrttle plates - ok, idled veh to 2000rpm to measure default air flow, plugged in MAF sensor to see response, system stayed running. Initially could not get proper rpm, air flow measurement, idle stability, fuel trim stability. Adjusted TPS to 0.66v from 0.55v, stabilized fuel trim and idle. Had codes 33, 34, 36, pertaining to low voltage MAF, high voltage MAF, and afterburn. Code 34 continues, relating low voltage MAF sensor. 3.0 hours

So I'm SOL. They said that the only real way to get it back to 100% is to buy a NEW MAF sensor.....I think its time I do..... New will cost $1970.00 + Tax and still a month away from my wedding

y84pauloflondon

VERY UNLUCKY I GUESS, SOL.....lol

y84pauloflondon

I did ask them to check all relays, connections and loose wires, they said they did. I believe them, but could they have missed one or so by chance. remember that they have had my car there for about 7 or so hours (tech time)!

Chevy8588

iTrader: (1)

something is NOT right here... take it to another chevy dealer, get another opinion

y84pauloflondon

Well should I spend the $$$$ and get new maf, see if that makes a diff?
Or just take it now to a diff dealer?

My brain is melting....lol

Chevy8588

iTrader: (1)

find a buddy with a running MAF Bird or T/A or even camaro, test your MAF on his car, if it runs fine without codes, then there is a problem with your electrical system, one red flag im getting is an aftermarket ECM. what I would do is rather than continue condeming MAF sensors, I would test it on a normal running vehicle, if it works then i would pull that vehicle's ECM out and test it in your vehicle, a MAF reading is only as good as the ECM recieving it. also without reading your knock sensor your EST will not work right, giving you other problems. if this system of tests works out and it turns out to be your ECM then I would go to the dealer and WTF them for not checking into it.

y84pauloflondon

In the last 9 yrs of owning my car I have only seen 6 GTA's in my area, that really doesn't matter. I need to find someone with a 86-87 5.0L or 5.7L TPI's.

Don't know anyone with those.....do you think a stragner will let me swap parts out???LOL

But that is a really good idea though!!!

y84pauloflondon

Time to make new friends....lol

y84pauloflondon

Chevy8588- what should the gm's/sec be at 650rpm's?
- Is a pcm the same as a ecm with a aftermarket chip? or is pcm an aftermarket ecm?

Chevy8588

iTrader: (1)

Notes 88pontiac01
Number 87-6(Gasoline)-83 Date 1/88 MASS AIR FLOW (MAF) SENSOR SYSTEM DIAGNOSIS CODES 33, 34 AND 36 Subject: 1986-87 FIREBIRD MODELS EQUIPPED WITH LB9 OR L98 ENGINES Some vehicles equipped with 5.0L or 5.7L port fuel injected engines may experience "Service Engine Soon" lights with some combination of codes 33, 34 and/or 36 stored. This bulletin summarizes diagnostic procedures to be used in troubleshooting these codes. All 1986 model year vehicles should be updated to the latest service PROM per bulletin: 86-6G-66 and checked for "Service Engine Soon" light reset prior to further diagnosis. The MAF power relay should be checked to assure that it is part number 10067925. If it is not, then it should be replaced with part number 10067925. Please do not substitute.
DIAGNOSIS
CODE 33 (MAF SENSOR VOLTAGE HIGH)
1. Inspect to determine that part number 10067925 relay has not inadvertently been installed as a burnoff relay or incorrectly connected as a burnoff relay. (reference Bulletin 87-6G-57) NOTICE: SOME SERVICE PARTS BOOKS REFLECT THIS INCORRECT USAGE. For proper relay parts usages, please refer to the relay usage chart provided at the end of this bulletin. No substitutions, should be made.
2. With the engine fully warmed up and operating in closed loop, check the airflow at 2000 RPM in neutral using a Tech 1. If it is below 16.0 gm/sec for a 5.0L or below 18.0 gm/sec for a 5.7L engine and the block learn value is greater than 138, replace the MAF sensor. If code 33 still resets, refer to section 6E of the appropriate service manual for further diagnostics.
CODE 34 (MAF SENSOR VOLTAGE LOW)
1. Inspect the plenum side of the throttle blades for deposits. If even a small amount of deposits are present, clean the throttle body per Bulletin 87-6G-30. 2. Thoroughly inspect the vehicle for sources of air entering the engine without passing through the MAF sensor. Specifically, look for a cracked, cut or loose duct between the air meter and the throttle body, poor inlet runner to plenum or manifold sealing, a split PCV hose or any type of vacuum leak. A large quantity of air does not necessarily have to be involved. If any leaks are found, repair the condition, clear the codes and check if the code resets. 3. Check resistance of the MAF power relay contacts per bulletin 87-6G-31. The resistance should be less than 1 OHM across closed contacts. If the resistance is greater than 1 OHM replace the relay. 4. Check the minimum air rate and compare to specifications found in Bulletin 87-6G-30. If the air rate is below specifications, please reset by connecting a vacuum gauge to port A on the throttle body, increasing the air rate by turning the minimum air screw until one inch of vacuum appears on the gauge and then reducing the minimum air setting by one half turn of the screw. If Code 34 still resets, refer to section 6E of the appropriate service manual for further diagnostics.
CODE 36 (MAF BURNOFF) 1. Inspect to verify that the MAF power and burnoff relays currently on the vehicle agree with the usage chart provided at the end of this bulletin. 2. Check the relays for proper function per bulletin 87-6G-31. Also, check for PCV plugged condition per the same bulletin. 3. Check all electrical connections carefully. If Code 36 still resets, refer to section 6E of the appropriate service manual for further diagnostics.
RELAY USAGE CHART:

YEAR MODEL POWER RELAY BURNOFF RELAY 86-87 FIREBIRD 10067925 10094701

Chevy8588

iTrader: (1)

Number
87- 6 (Gasoline) - 91 Date 8/88
Subject: CODE 33 MASS AIR FLOW (MAF) SENSOR VOLTAGE HIGH DIAGNOSTICS (DIAGNOSIS) 1986-87 FIREBIRD MODELS WITH 5.0L AND 5.7L ENGINESome vehicles may experience a check engine light with a Code 33 stored which cannot be easily diagnosed. To promote better diagnosis of this condition, a brief explanation of the criteria for setting a Code 33 and an explanation of the possible causes follows. Before beginning diagnosis, all 1986 models should be updated to the appropriate service PROM listed in bulletin 86-6(Gasoline)-66, dated 10/86.
Mass Air Flow (MAF) power and burnoff relay part numbers should be checked to assure that they agree with those listed in bulletin 87-6(Gasoline)-83, dated 2/88.
Code 33 is set when the voltage at Pin B12 of the ECM exceeds 2.2 volts for 1 second or more either at startup or when the Throttle Position Sensor (TPS) is less than 20% and the RPM is less than 2000 RPM.
The ECM provides a 5 volt signal at pin B12 through a pull up resistor. This voltage must be brought below 2.2 volts by the MAF sensor circuitry during the conditions mentioned in the above paragraph or a Code 33 will set.
A condition whereby the MAF sensor circuit can not accomplish this can be caused in the following manners:
- An open or intermittent in Circuit 998 (dark green wire from ECM pin B12 to MAF sensor pin C) . - A condition causing voltage at MAF sensor pin D during crank or run such as: ^ A short to ground in Circuit 900 (black wire from ECM pin D12 to MAF burnoff relay pin F). ^ A faulty or incorrect burnoff relay. ^ A short to voltage in circuit 994 (dark blue wire from pin A of the burnoff relay to pin D of the MAF sensor). - A condition causing reduced voltage supply to pin E at the MAF sensor such as: ^ An open, intermittent, or short to ground in Circuit 993 (red wire between pin E on the power relay and pin E on the MAF sensor). ^ A faulty or incorrect power relay. ^ A faulty fuel pump relay. ^ Poor or intermittent ground on Circuit 450 (black/white ground). ^ Circuits 340 or 120 intermittent, grounded, open or spliced into with anything which draws enough current to lower the voltage by 2 volts or more for a 1 second period. This includes but is not limited to CB radios and alarm systems. (Circuit 340 orange extends from ECM pin B1 to MAF power relay pin A and fuel pump relay pin E; Circuit 120 tan/white extends from fuel pump relay pin A to MAF power relay pin D) . ^ An intermittent or low TPS switch causing the ECM to run a Code 33 check at a higher throttle angle (and therefore higher airflow rate) than specified. ^ A faulty or poorly connected MAF sensor. As evidenced by the above list of possible causes of Code 33, this circuitry is very sensitive to minor wiring discrepancies and poor or loose connections. All connections should be checked carefully. One method is to wiggle the connections while meeting the conditions for running a Code 33 test as listed earlier in this bulletin. In addition, they should be inspected for corrosion and/or bent pins.
This bulletin is intended to provide supplemental Code 33 diagnostic information and is not intended to replace the Code 33 diagnostic chart in the Service Manual.

y84pauloflondon

Chevy8588:-Please read post# 78.
Hooked up my buddy's laptop, MAF reads 10gm's/sec at 625-650rpm. Does this sound right to you? (TPS is NOW set at .66v)

Chevy8588

iTrader: (1)

run it up to 2000 RPMS and if the GM/sec is less than 18.0 AND the Block learn is GREATER than 138, the MAF is malfunctioning, there is no SPECIFIED GM/sec at idle due to variences in vehicle air flow, the TSB's i posted show how to trouble shoot your codes as GM defined them. though I'm still wary of your ECM

WileECoyoteSr

I'm glad I started this thread because we've bounced a lot of good ideas around. As for my Z - IT MAY BE FIXED!

Paul - I am happy to report that since replacing the entire distributor last wednesday, I've put a couple of hundred miles on the Z-28 and started it probably two dozen times and it's started every time.

I elected to put a complete OEM replacement type distributor in instead of replacing just the magnetic pickup sensor. When I took the old distributor out it looked to have just normal arcing dust dirty. It wasn't any sloppier than the OEM replacement unit. Therefore to look at it you couldn't tell if it had anything wrong.

I timed it up to specs and it starts and runs like a top. My advice is to spend the money for a new distributor and replace it with ignition module and magnetic pickup complete (US$99 Autozone for reman). It took me longer to tighten back down the hold down bolt than it took to R&R the units. I didn't have the right wrench and had to use an open end aiming down from the top with a screwdriver to turn the boxed end. Caveman approach, I know. But it worked.

Thank you to all who offered their advice. But try replacing your magnetic pickup (distributor). It evidently has a key command in the start sequence within the ECM.

Now if I could only get the gasoline smell to go away. Per another thread I took advantage of the GM recall on the gas tank neck and had a Chevy dealer inspect it today but all was well with the neck to tank weld. Something else is causing it to smell like raw gas from time to time, and I even got some gas residue on the rear quarter below the fuel door yesterday. Hmmmmm??

Chevy8588

iTrader: (1)

over time, the mechanism in the fuel filler cap loosens, it won't tighten, and will leak, replace your gas cap. and good to hear the distributor worked for you too man!!!

y84pauloflondon

Hey WileECoyoteSr....I Hope you are NOT a smoker.....

y84pauloflondon

UPDATE......... I think I just did it. I just finsihed replacing both MAF Power and MAF Burnoff relays.Started it and...............No codes yet

Its been running for 15 mins and no codes.....

When it rains, it pours......but when it stops, the grass is greener and everything is cleaner....

y84pauloflondon

Well, TPS is reset too 0.54v. Started it up again on the first try......No codes, and let in run for 25 mins. And even gave it some GOOD revs. Some of the neighbors din't like that, but................So what, feels good to have Her back up and running.

WileECoyoteSr

OUTSTANDING! Congrats.
I understand your frustration with the dealership. Now can I share something with you? I grew up in a family Chevy/Buick dealership and was many times tasked with shaking and pulling on wires (including spark plug wires back then) while the service manager watched for the customers car to act up. Been known to ride upside down with my head under the dash board while the SM drove and I tugged on wires looms. Electrical problems were enough that one car my dad actually bought back from the customer because we couldn't fix it.

The dealer and his techs can only do so much and unfortunately for all of our sophistication we've built into these modern go machines, we don't have any one machine that will tell the tech - yup! you've got a dead thingama jiggy!

WileECoyoteSr

Actually the fuel smell got worse when I bought and installed a new gas cap. But I got it from AZ, it was only $8, and I opted for the fancy locking type. The new caps physically leaks fuel return mist evidently and so I'll be taking that back. Tried to get a genuine GM from the local Chevy dealer for only $18 but they no longer stock anything older than a 93 and they are supposedly different. I'll call the other Chevy dealer across town and then the one remaining Pontiac dealer before I go to AZ's competition for another cheap gas cap. I guess it's another "you get what you pay for".

WileECoyoteSr

You know you need to take her out and "SMOKE EM".

Chevy8588

iTrader: (1)

make sure you try turning it in slowly too, on mine if i dont to that and just slam it in fast it will not seeat and leak

WileECoyoteSr

Yes, I tried turning it in slowly. Made it click three times at least as recommended. Still got the fuel smell. Inspected it and seal is good.

Chevy dealer didn't see anything wrong with the fuel neck when he did the recall inspection. I'll try putting a genuine GM cap on it. This fancy locking cap is probably junk.

y84pauloflondon

OH YEAH...........

Unfortunately Cutlessman14 and I had plans of going to a local car show this past sunday and meet eachother there for the first time. Well we both had problems with our cars and didn't.......That was the last show of the season.

Chevy8588

iTrader: (1)

could be the tank vent too

y84pauloflondon

Has he mentioned if the smell is coming from the front or rear of the car?
I do remember that he had a leaky gas cap, but the smell was b4 that.

WileECoyoteSr

The Z is starting every time, hot or cold. I really think the distributor change solved my problem and once again thanks to all for their ideas.

I found my fuel smell - well two sources. Since I'm supposed to be fixing this old Z up for my beautiful granddaughter to "buy" from me next March when she has her 15th BDay, my son mentioned that the exhaust sounded like it had a number of leaks. So today I took it to a really good custom exhaust shop and for $106 they fixed all the leaks. Off subject I know. But these guys don't hold to the no customers in the shop sign and I got to do my first intense inspection of the under side of the Z.

THE GOOD NEWS is that just as I had been counseled by you guys I checked every fuel supply and return hose and way up there above the axle one of the three smallest rubber return or vent hoses showed recent fuel leaks had washed it clean while the others had the normal road grime. I'll crawl under there and get that one replaced as soon as I can but I hate those OEM spring clamps!

THE BAD NEWS is that I could easily see fuel stains on the filler end of the tank and I just got it back from the Chevy dealer who did the safety recall. They weren't wet, but then it's been ten days and almost 200 miles since I filled the tank. If I could readily see it, why couldn't the Chevy dealer tech who signed off the recall see it?

I pulled off the fuel door and boot and I can easily see that the putty around the fuel filler neck to tank junction has been fuel soaked in the past. As a matter of fact some of it is flaking off now that the tech supposedly inspected it. I know that the putty only covers the weld. But that tells me I have a bad weld which was the purpose of the recall. It explains why if I fill the tank past when the gas pump kicks off the first time (we can still do that in Kansas although I know many states outlawed such practices) I get a raw gas smell.

I will be placing a call to the dealer's service manager tomorrow and if they don't take it back in and fix it I'll simply call both GM's recall satisfaction hot line and the National Highway Safety Administration.

Just thought I'd update you'all.

Chevy8588

iTrader: (1)

get the service manager on the line and explain to him his tech is wrong, if he decides he does NOT want to work with you, demand the number to their GM regional service rep and GM corporate, and file a complaint with both, giving them the technicians name and number from your copy of the RO. and since you are states side also file a complaint with the better business bureau, also make it a point to state you have obviously leaking fuel lines underneath the car that the tech failed to find, so therefore he didn't do the 21 point good wrench inspection completely

WileECoyoteSr

I'll certainly push them about it. The Safety Recall print out from the National Highway Traffic Safety Administration lists right there the contact numbers for GM AND the NHTSA that you can use to report the dealer. I'll simply show the Service Manager the text on the government's version of the recall, the photos I took at the muffler shop today of the evidence of fuel leakage and ask him how he's going to handle it. Since the Z is my spare car I'm not paniced over it.

quick90rs

iTrader: (3)

can i be the one to say go carbureated!

WileECoyoteSr

Quick90RS - I hear ya. Rochester quadrajet howling was music to my ears until I could afford my first Holley 650 CFM Double Pumper. Plugs, Points, Condensor and a fuel filter was all you needed to keep a car running in the 60's and 70's. Now those in the know are riding with laptops.

But I have to admit, when a fuel injected engine is set up and working right it beats the heck out of fiddling with the choke plate and adjusting secondaries. Come to think of it, my Z-28 L98 with TPI is equivalent to an engine with "Dual Quads" but burns way less gas.

It you got the skills, more power to you brother. Enjoy the ride.