OK when I scaned the computer with a EZ-READ 2000 and im getting a code 15 coolant sensor is too low, 34 MAF/MAP SENSOR TOO LOW, AND 44 OXYGEN SENSOR LEAN... But I just replaced the MAF and the Coolent sensor today.. how do I clear out the old codes on this thing? its a 88 with a 2.8 and a 700R4

 

Disconnect battary for about 30 seconds then reconnect it simple enough!!!

Kyle

 

isnt it 15-30 mins to clear the codes

 

only took a 30 second disconnect when I cleared mine.

 

all that has to be done is the capacitors in the computer need to drain and the puter dont have no battery so 15min is way over kill.

 

remove both the - & +

Why?

Ya allways remove the - first and put
it on last so not to create sparks. Safety 101


There is a point though that as long as your car runs good.
I would ignore them coded. Listening to them codes can run you in a circle of spending cash. Them computer aren't very smart but they can help give you clues to your problem. Just don't consider them set in stone.

 

OK the only code I have left is 44 OXYGEN SENSOR LEAN.. Will this couse the engine to die at idle ?

 

The codes should clear during the code scan. Pretty much all other OBD-1 GM ECMs have this trait.

 

the real pain is that the code 44 is intermitted and its making it hard to chase down..

 

Wow.

You guys never cease to amaze me. You'll spend the money on the car, you'll mess around with all sorts of nonsense trying to make a V6 into a performance platform, you'll talk turbo's and 3.4 swaps, yet it seems that none of you are willing to step up to bat and buy a damned service manual.

EBAY IS YOUR FRIEND! Spend $30 on the manual for your car and use it to troubleshoot your codes. Seriously, instead of posting on a board and hoping that someone knows exactly what you need to do, you just grab your manual, look up the code and it gives you flowcharts, wiring diagrams, diagnostic tests, etc. Follow those steps exactly and it will lead you to the solution. None of this finding a random definition online or in a Chiltons or Haynes and then buying part after part at the parts store to try and fix the problem. Even if you have to buy a service manual new from Helms its still going to cost you less in the long run then having substandard information.

It's really quite simple. I really love the comment about ignoring the codes... That's true genious at work. The ECM isn't very smart, but it isn't going to alert you to a problem that doesn't really exist. If that light is on, then something isn't within spec. Ignoring the codes is for ignorant single mothers that have the wrappers from the last 50 trips through McDonalds ground into the carpet in the backseat.

 

 

QFT!!!!

 

Hey Drew,
I have order one.. It just hasnt gotten here yet and I dont want to wait intill it gets here in 2 weeks to drive my car..

 

since it doesnt look like anyone answered your last question, yes the O2 sensor can cause your car to die at idle if its running lean. Thats saying your a/f ratio is off. Intermittent issues are a pain to hunt down, but since the o2 sensor is fairly easy to get to and doesnt cost a lot, I suggest replacing it to see if it goes away. If not, you may have a more serious issue.

Drew, it amazes me how you just called a bunch of us idiots yet you give this person NO help whatsoever. Now, I am a single mother, I work full time as a service tech and my SES light is on in my camaro too. But Im the ignorant one. Oh and the code...its to a problem that doesnt really exist. Just a bad wire.

 

I've never seen an O2 cause a vehicle to run so lean that it dies. The way that GMs are setup is that they have a limit in the block learn that only allows the O2 to adjust the fuel so low. That limit is still FAR within the safe range to run an engine. Now...changing the O2 is a good idea just becuase most people neglect it and it probably needs replacing anyway, but it's more than likely that it's not going to solve the problem.

Quote:

Oh and the code...its to a problem that doesnt really exist. Just a bad wire.

A bad wire is a problem in the circuit. Since the light is on, the computer knows there is a problem and is substituing a value for whatever signal it's not getting. Now, don't take this as an attack on you or a defence of Drew, but people shouldn't think that a bad wire isn't a prolem. The problem exists, you say you know what it is, and as a tech, you should have the resources to find the protion of the wire that's bad, and repair it so the light doesn't stay on. I would suggest repairing it now, because if a "real" problem does arise and sets the light, you'll never know because the lights been on long enough that you just ignore it.

Remember, our computers only point to a problem cicuit or system, not one specific component. It's the person working on it's job to find out what needs to be replaced/repaired, it just points us in the right direction.

Now, in answer to the Code 44, the O2 sensor has been reporting a LEAN condidtion for a while and the block learn memory is pegged as rich as it will go. Even with the ECM adding as much fuel as it's allowed to, the O2 is still saying lean. There are MANY reasons for this.

The fisrt thing I always check for is vacuum leaks, take a can of carb cleaner and spray the intake area AND the EGR area to see if the engine RPM raises. If it does, there's a leak in that area and you need to fix it. Leaks downstream of the MAF sensor cause poor idle quality, stumbles, hesitation, Lean Codes, and shutoffs at idle. You could also try blocking off the Brake booster because even a small leak there could cause problems considering how much vacuum is stored there.

If all checks out there, check your fuel pressure. Low pump output or a bad regulator could cause a LEAN condition because INJ PW are calculated and rely on a minimum pressure at the injectors to deliver the correct amount of fuel.

These are the easiest to check for and I started with the cheapest. Other things are bad MAF(which you just replaced), bad CTS(also new), bad/lazy IAC, clogged injectors, bad injector ground at the ECM...you get the idea. The stuff above are the most commen problems for a lean code.

Something that would help is knowing what goes on right before it dies. does it surge and hunt around? Will it idle at all? Does it surge while cruising? Please feel free to add any and all relavent info as it's needed to find out what's going on.

Good Luck,
Jeff

 

ok here how its been going..

Idle about 950 RPMs.. and no SES light.. drive for a some time.. can be 10 mins or 3 hours.. Very random.. And then the idle will drop to just barely 500 RPMs and the SES will come on.. and its will be ruff running and die at just about all lights.. than sometime the SES will turn off and everything back to normal.. One thing I have notice it when the SES does come on the temp will climb to about 220* but when its off its about 180*... Dont know what cousing this.. I have been driving aroung with a scanner doing live runs and all I keep getting is Code 44.. every else looks good.. Also did notice that the exhuase Y pipe is crush to about 1./2 its size ( bottem out) and there a tear in it about where the O2 sensor is..

 

Also.. what should this stock 2.8 be running at ( temp wise ) anyway?

 

An exhaust leak before an O2 sensor will cause it to read lean. Now the ECU thinks youre lean, is dumping fuel.....you know where this is going. Though this shouldnt cause your running hot problems, lean is hot, rich isn't. So your O2 might be telling the truth. Maybe youre getting a major fuel cut back, like your fuel pump is wigging out on you but not badly enough to shut the car down

 

Well, I got a new Y pipe and a new O2 sensor today.. will be installing them asap.. But what should I running at for a engine temp?

 

Mine sits at about 200 in traffic and about 190 when cruisin down the highway!!

Kyle

 

Fan on idle is 190* and on the road is about 185*. But stock it is supposed to sit right about 210*/220*. the fan turns on at about 225* and stays on till like 210*. on the running crappy for a few and then going back to normal i had some wiring that was shaking and loosing contact for short times. fixed that and i had a ECU go bad cause of that and it did the same thing.

 

OK.. changed the Y pipe and the O2 sensor.. here what I found in the process..

1. Both Ex. Madifold to pipe donots missing..
2. Driver side pipe rotted thru on the block side..
3. Some dumb *** punched out the cat ( AGGG more to buy )

Now the code 44 dont show up and the idle is better.. But it still dies for no reason I see at idle ( randomlly ).. does anyone have a idea what may couse this??

 

Well after calling around I find out a cat will cost me about $176 (OUCH!!) does anyone know if a 88 2.8 can get by cali smog with out a cat? the housing there.. just punched out.. If so tips would be handy here.. I have 10 days to get this smoged now and not the cash ...

 

hey i can sell ya a hi flow perf cat for liek 50+shipping if u can pass with that

 

tell U the truth.. I just dont know.. I have lived in cali for about 6 years now.. And I hate the smog laws here.. when the guys say smog ****'s, thay are not kidding.. My wife car wouldnt pass becouse of a warm air duct was missing.. and becouse the PVC filter was not OEM.. 2 $.50 parts and thay charged me $40 and wouldnt pass it.. where I come from the smog tech would have put on the parts and than said have a nice day.. ( Thats back in Mass) but here thay cant fix or adj anything except the gas cap .. And yes U must have the right and good working gas cap here ...

But that price sounds good.. I wonder what shipping to Ca would be...

 

wow if its really that bad i dont think u would pass with one of these cats then caus eit dosenty look like an oem cat, it looks like a bullet muffler, but it is a fully functioning cat.
i forgot that ca does the visual inspection, i dont have to deal with that in new jersey, hell i just got my friends 358ci 425hp el camino threw state inspection, full race headers,wildcam no cats flowmaster race muffles and turnouts
pretty much the same engine i built for the rs except mine makes more power

 

Its bad .. Like when I first moved out here.. I bought a 86 ford ranger.. It keeped throwing a code for a TCC failure.. A code for a auto tranny problem.. But it had a 5 speed.. after 3 computer and about $1000 it still wouldnt pass.. so I junked it and bought a 60 F-100...

 

ouch that is bad it is liek that here in new jersey to with the codes,but we get away without having visual inspec so its easier to sneak stuff threw, though my rs failed for ex system ,(to loud) tint,tach on the pillar(obstruction of view) and suspension,(have a really stiff suspension so it failed on the shaker machine),and emmisions, though i went to a local garage paid 150$'s and they passed it so im good for 2 more years,but by then i wil have hotrod plates on the car and ill drop the 358 in it and wont have to worry about emmisions inspection

 

So from where I left off.. does anybody know if a 88 2.8 can squeeze by smog in cali without a cat? and also does anyone have a guess why it still dies randomly at idle?

 

see it seems to me that the more i hear about these emisions laws from all of you is that 90% of yall just take your car to a buddy or a sneaky shop and get out of it. Its just like half the crap in this country right now they make the laws so strict and crap to keep this stuff down but all it does is makes it harder on the honest person and dont affect the not so honest. like the guy with the 2 tiny parts and he couldnt pass, but the other guy with a crap load of violations got out of it by going to a dishonnest shop. that just makes them make the laws that much harder on the normal honest people to try to stop that kind of crap. and if you have a visual obviously no. if your car was running perfect with a brand new engine IE no wear on it mabe you could pass the sniffer but chanses are like 1 in a million. i now you have probably heard this a milion times but check the vacume. get a Vac gauge and see what it reads ok? even a small leak will cause the car to die at a stop most of the time. i speak from experiance my car had all origional hoses i changed them all it fixed most of it but it kept dying on me so i looked and looked everywhere and i found i had a tiny leak right by the char canister caused by one of the lines i put on. the lip had curled over and had created a leak about the size of a pin head, i fixed that and it has yet to die on me again.

 

Ya its sad when others buy there smog and than make it harder on the honest people.. I dont want to cheat my way by.. its than right now I just dont have the money for a cat and I need to get this car past smog somehow.. Looks like its gioing to be off the road intill I can rise the funds.. I have in the past gotten other cars past smog with a punched out cat.. but thay where older and with great running engines..

 

ya still got bunch of exhaust leaks? O2 sensor doesn't work until its gets hot. If you leaking to much exhaust it may not be building enough heat to read.

 

Im sorry.. I thought I siad I found the problems as I fix them.. IE: bad ex gaskets, holes, and otherthing in the Y pipe.. I replace the whole Y pipe all the way to the cat.. found out the cats been punched out.. and I just paid $170 for the new Y pipe and a new O2 sensor..

 

id put a volt meter on it and get your own O2 readings while you drive.

red to O2 wire, black to ground.