Ok .. I have replace every thing I was getting a code for.. Replace all the VAC lines and fixed all the vac leaks I found.. than I reset the timing, and adj the TB. but Im still getting bad milage and at Idle it sounds like its loading up...

Any tips would be helpfull..

 

Well, I could tell you to do a for the famous TomP tuneup, but I'll give you the condensed version:

Replace Cap, rotor, wires, plugs (AC/Delco R42TS plugs)
Replace ALL filters (auto trans, fuel filter, air filter, oil filter with AC/Delco PF 47 or the larger one, can't recall that number at this time)
Change ALL fluids (engine oil, rear end oil, ATF or manual trans lube--also ATF, coolant)
Check timing
Check tire pressure
Replace oxygen sensor in engine crossover pipe (biggie here)

Note the color of the plugs to determine condition of engine health. If they are anything other than either tan or grayish tan, even if there is plenty of electrode left, replace them ($2/ea can't hurt if you are trying to pass CA smog testing).

Now, note increased gas mileage and happier engine (better acceleration) and happier you...

 

A full tune up.. I'll give it a try.. cant have it keep stalling at lights.. thats so annoying

 

Ok gave it a full tune up.. and its still acting like its it wants to die at idle.. Plugs did look good.. still rplaceed them tho

 

check o2 sensor and maf sensor

 

Both are new.. and im getting no codes.. Its driving me nuts....

 

if it feels like it loading up maybe your cat is clogged.

How fast have ya gone latley? Maybe try blowing it out. Rev each gear manualyto near red line and just push it.

 

The cat new.. and before the cat was install( Had a punched out cat) it acted like it was loading up at idle.. And I live in a area where most drivin is highway ( 65mph - 75mph) and mountainios...

 

how is the rest of the exhaust???

junk can collect and clogg the muffler too.

 

maybe hook a volt meter up to your O2 n get some readings yourself.

see if its fuel load or not.

postive of volt meter goes to O2 wire, ground goes to ground.

maybe take someone with ya and record the readings while you drive.


if it not fuel, could be timing or something is restricting flow.


read this for basic info on O2 reading


http://www.bob2000.com/carb.htm

 

The exhuast is new form the block all the way back.. It was a real mess when I bought it.. Can a live reading be done from the OBD connector? I have access to a Scan tool 6000 that will do live reading( I know from OBD2 ) but dont know if the OBD1 can do it?

 

I dunno, id just use a cheap $7 volt meter

 

Voltmeter I have a few of them.. a ride alone buddie.. thats a diffrent storie...

 

Well I just said that to be "PC" safe cause someone would of posted other wise.

I thought of perm mounting one in the dash. But just display the LCD part n hide the guts behind dash. But for around $30 yo ucan get a rich lean mini gauge, just not as accurate as the volt meter.

but its usually fuel load, timing load or flow load

 

this car was a real mess when I got it.. al the sensor where bad.. the Dizzy timing was way out.. almost 30* at idle.. and the TB setting where all messed with.. And this is my 1st time messing with a computer driven car.. All my others are pre 65..

 

yea, its a PITA plus these computer aren't very smart.

sure its nutin else? tranny, rear end, wheel bearings, brake drag?

 

off idle it runs great.. heck.. it has 235/50.15z tires and it will smoke them right off the line.. Just at idle its real ruff and dies.. it seems like it cant hold the idle.. And its does seem to go thru a lot of gas.. milage is **** in it.. really cant fig it out.. I had the whole top end off and replace all that gaskets ( vac Leaks ) and all the vac lines.. Got it so it wasnt idleing at 1500 now its idleing at 800.. but will all a suddunly drop to below 500 and just die.. starts right back up with np.. and its not throwing any codes.. so im at a lost now..

 

sunpro a/f gauge 25$ at autozone

tested mine against an auto meter gauge and they both get the same readings though the sunpro reacts a tad bit slower then the autometer

 

Dont get me wrong here.. But I hate Autozone.. and besides. I have accounts at NAPA and Kragen (Proshop)

 

there ya go, put cold idle back at 1500, not suppose to manualy play with stop screw.

car should idle high cold then drop when warm.

when really really cold mine will rev up n down from 1000-1500 till warm then be normal. In decent temps it will idle smooth around 1500 then drop later. its normal.

 

they prolly carry the gauge also i personally try not to buy stuff from auto zone or pepboys, places like that etc,rather deal with a real parts place were someone behind the parts counter knows about cars.but u still cant beat the other places for general stuff

 

I set the Idle as the chiltons manual says to.. and it wants it set to 550 with the set timing disconnected.. and once I have that done it idle is at 800rpm with every thing reconneced...but If im at a stop light for more than a few mins it will all sudden drop to below 500 and die.. idle while in park is ok most of the time.. just once in awhile it acts like its loading and dies..

 

that just to low, your not riding a HD.

its gonna lag n die

 

Thats what i thought.. But I have to have the RPM in spec to pass smog also.. And All I can find in the chiltons book is how to set the rpm and it wants it set to 550rpms with the IAC disconnect and the set timing disconnected .. What I need to find out is what is Spec for this car at Idle in Ca to pass smog and than I can set it to that..

 

I think most people only set their cars for smog to pass then retune.

smog settings suck

 

what sucks is thay charge you $45 no matter if it passes or not.. and thay have stopped doing pretest.. What I need to find is someone who has a 2.8 MPFI camaro around here so I can see what there setting are so i can copy them and pass smog.. than its on to the light and brakes test.. Ho the fun...

 

1. You are NEVER going to reach the factory spec idle speed without stalling. BTW: factory spec idle speed for my 87 2.8 with auto trans is 700 RPM when at operating temp. DO NOT set the idle speed cold, as the engine will stall when hot and the ECM drops the idle speed (unless it's my engine, of course, where the idle speed rises with the CTS temp). LEAVE THE TIMING CONNECTOR ALONE UNLESS YOU ARE SETTING THE TIMING.
2. Clean the IAC passages in the throttle body.
3. Check the vacuum tee (that runs the brake booster) for possible leaks between itself and the plenum. Check the booster's check valve while you are at it. Also check the vacuum tank by d-con'ing the vac line and plugging it.
4. Check the injector o-rings for damage.

BTW: Chilton's and Haynes sucks. They are good for the basics, but not much more than that.

:edit: Also, don't rely on the factory tach too much. Mine is about 200 RPM off (or the speedo is off, reads about 250 RPM high at 60), and others have been known to be even farther off.

 

All the Vac lines are new.. brake booster vlv is new.. and the TB been fully rebuilt.. This what Im going nuts.. Just about everything is new.. I cant tell if the IAC is working and I still havnt found a way to test it..

 

Have someone cycle the key on and off with the hood open and listen to it. If it makes a noise when the key is cycled off (it's closing to richen the intake charge for easier starts) then it's good. If not, either the connector is loose, the IAC is bad, or your ECM is at fault.

:Edit: Get yourself a can or two of starting fluid and start spraying near all vac line connections. If the engine runs better when hot with the fluid sprayed on a connection, that connection is leaking. Also, check the vacuum valve on the charcoal can to see if it has a vac leak, same with the EVRV (the solenoid for the EGR valve). Be careful of the MAF, as the starting fluid destroys it, and of the exhaust parts.