dirtydevin Posted December 17, 2011 Report Share Posted December 17, 2011 I read the fsm and tried to check the ecu diagnostic codes, but all I get is the meter going back and forth from ov to 12v every 2 seconds. There is no break in this pattern. If there are no codes the fsm says you will just get a constant 12v on your meter. What could be wrong here? Quote Link to comment Share on other sites More sharing options...
Spooled_Starion Posted December 17, 2011 Report Share Posted December 17, 2011 Go get an led from radio shack and plug both ends of it into the port in glove box and it will blink the codes for you!!!!! Quote Link to comment Share on other sites More sharing options...
Ironside Posted December 17, 2011 Report Share Posted December 17, 2011 http://www.starquestclub.com/forum/index.php?showtopic=28043 Quote Link to comment Share on other sites More sharing options...
Spooled_Starion Posted December 18, 2011 Report Share Posted December 18, 2011 Also make sure to check your codes at full operating temps or else you could get a O2 sensor code. Quote Link to comment Share on other sites More sharing options...
Indiana Posted December 18, 2011 Report Share Posted December 18, 2011 To see what the ECU receives as input signals you can look in the ECI checker pages in sect. 14 that will tell you the pinouts and what voltages they expect to see. You only need a cheap volt meter. There are 4 pages that tell what you are checking and the position of the ignition switch, if the motor has to be running etc and there's also a wiring diagram and a ECU diagram showing the pinouts and their id you'll need to reference also in sect. 14. When the wiring diagram for the pin you are checking uses the "sensor ground" pinout for that sensor then that's when you use that (the "sensor ground" pinout) for your ground otherwise you use the body ground. Quote Link to comment Share on other sites More sharing options...
dirtydevin Posted December 18, 2011 Author Report Share Posted December 18, 2011 It looks like I was just getting the o2 sensor code over and over, but I did have the car warmed up. I have a fairly new 3 wire o2 sensor, and read that it may not recognize the 3 wire the same? Anyone had this problem with 3 wire 02 sensors? Quote Link to comment Share on other sites More sharing options...
Spooled_Starion Posted December 18, 2011 Report Share Posted December 18, 2011 It looks like I was just getting the o2 sensor code over and over, but I did have the car warmed up. I have a fairly new 3 wire o2 sensor, and read that it may not recognize the 3 wire the same? Anyone had this problem with 3 wire 02 sensors? I'm pretty sure starquests don't use a heated O2 sensor, and generally use a 1 wire O2 with a ground on ecu end. Quote Link to comment Share on other sites More sharing options...
Spooled_Starion Posted December 18, 2011 Report Share Posted December 18, 2011 It looks like I was just getting the o2 sensor code over and over, but I did have the car warmed up. I have a fairly new 3 wire o2 sensor, and read that it may not recognize the 3 wire the same? Anyone had this problem with 3 wire 02 sensors? I'm pretty sure starquests don't use a heated O2 sensor, and generally use a 1 wire O2 with a Shielded ground on ecu end. Quote Link to comment Share on other sites More sharing options...
traps Posted December 20, 2011 Report Share Posted December 20, 2011 I like having an LED light mounted in my dash to keep an eye on things and its so cheap and easier than getting in the glove compartment. I am a bigger guy so getting my voltometer in there was a pain and after a while i decided to do the LED light. I noticed after I replaced my leaking inj that i was getting rid of my 02 code faster, guess car wasnt running so rich and engine temp heated up faster. If the single wire like mine is not at the heat it needs it will continue to throw that code. Also as Indiana explained it to me all the codes do is referrence and issue area. Use the voltometer and the manual to run through the proper diagnostics as explained in the FSM. Voltage might be off or grounds corroded, wires old etc. I am curious why ya did the code check to begin with. Whats the issue? Quote Link to comment Share on other sites More sharing options...
dirtydevin Posted December 20, 2011 Author Report Share Posted December 20, 2011 I did the code check because I have been trying to figure out why the car runs rough under boost. I may try a one wire o2 sensor for a little while and see what happens with the codes then. Quote Link to comment Share on other sites More sharing options...
traps Posted December 20, 2011 Report Share Posted December 20, 2011 I did the code check because I have been trying to figure out why the car runs rough under boost. I may try a one wire o2 sensor for a little while and see what happens with the codes then.Have you replaced the existing 02? Rough under boost? Only in boost? or at a certain RPM range? Quote Link to comment Share on other sites More sharing options...
Spooled_Starion Posted December 21, 2011 Report Share Posted December 21, 2011 Have you replaced the existing 02? Rough under boost? Only in boost? or at a certain RPM range? Isn't the O2 sensor for boost only? Idle and part throttle is closed loop boost is open? Quote Link to comment Share on other sites More sharing options...
traps Posted December 21, 2011 Report Share Posted December 21, 2011 Isn't the O2 sensor for boost only? Idle and part throttle is closed loop boost is open? The actual issue with vehicle was never originally stated other than throwing a code so I figured a better discription of the issue would help. Sometimes we are quick to diagnose an issue without the whole story. I do it all the time and miss the simplist stuff, Thats why I post my issues and detailed as possible and appreciate the feedback from others. Quote Link to comment Share on other sites More sharing options...
traps Posted December 21, 2011 Report Share Posted December 21, 2011 If there is an exhaust leak low boost could be suffering and jerking too. Quote Link to comment Share on other sites More sharing options...
dirtydevin Posted December 21, 2011 Author Report Share Posted December 21, 2011 I swapped the o2 sensor out for a new 1 wire and now the o2 sensor code is gone and I am getting code 3 for the mas. I had a different mas on my car and it would die when you came to a stop, so I put this other one I had on and that cured my idle issue but it looks like this one has issues to. I hate to get a new replacement mas as I plan on upgrading the mas and a maft to tune this thing with the t3/t4 turbo I have, but I was told to get the car running well before doing the maft or I will play hell ever figuring out the problem. Quote Link to comment Share on other sites More sharing options...
Indiana Posted December 21, 2011 Report Share Posted December 21, 2011 If the engine stopped running with the key on, that causes your "code", meaning did it ever die? What have you done with your air filter? Your MAF isn't BAD, the car wouldn't run if it was. Quote Link to comment Share on other sites More sharing options...
dirtydevin Posted December 21, 2011 Author Report Share Posted December 21, 2011 The car idles ok now, and was left running after a 10 mile drive when I did the diagnostic code test, previous to that I dicconnected the battery to clear the codes. The car has a stock air box with a k&n drop in filter. The car will sometimes idle really low when you come to a stop and you have to blip the throttle then it settles to a nice idle, other times the car idles a little high and you blip the throttle and then the idle drops to around 850rpm and idles well. Before I switched to this mas the car would always die when you came to a stop, or let off the throttle with the clutch in. I have already done the tps and isc calibration and reset. The car just seems to be running a little rough under boost and will cut out around 4k to 4500 rpm if you go above 12lbs of boost. Quote Link to comment Share on other sites More sharing options...
traps Posted December 21, 2011 Report Share Posted December 21, 2011 To reiterate what might have been said, have you checked the play in the throttle cable and to see if there is a catch in it? If ya need to pedal play then something is loose or not springing back properly. What has been done to the TBI lately? Quote Link to comment Share on other sites More sharing options...
dirtydevin Posted December 21, 2011 Author Report Share Posted December 21, 2011 Yes I have a little slack in the throttle cable, I have had the top off the tbi to change out injectors, and just replaced the tps and did the calibration. I have also checked and cleaned up all the grounds to make sure the intake was not trying to ground through the throttle cable. I also verified the throttle plate being closed, so I know the idle screw is not in to far. The only thing I have not reallly investigated is the nose switch on the isc. How do you test or verify it is working and ajusted correctly? If there is nothing wrong with my mas why would it show a code for it and why does it run rough? I have worked on alot of cars that had driveability issues that still ran, and found the mas to be the problem. Usually testing them is not 100% accurate and it ends up being a little bit of a trial and error type of thing. Quote Link to comment Share on other sites More sharing options...
Leeintheconquest Posted December 21, 2011 Report Share Posted December 21, 2011 I thought my MAS was dead at one point as well and Mikec. explained it to me like this: Lee - the 87-later cars use the MAS as the primary input to the engine computer (ECU) for fuel calculations. With a dead MAS, it's often quite difficult to get an 87-later car to even start. If your car starts with less than a couple seconds of cranking, and basically idles and runs, odds are the MAS is actually okay. The ECU's "MAS error" code just means the output of the MAS once upon a time indicated less than normal airflow going into the engine. This can happen for a number of reasons:1: MAS really is bad2: air leaks between MAS and intake manifold so the engine got air from some source other than the MAS3: the engine RPMs got really low for some reason - the engine was near stalled - which can happen for all sorts of problems including a klutzy stick-shift/clutch operator. Note too that the ECU does not clear the error codes when the problem is fixed... once the error is "logged' by the ECU it stays there until you disconnect the battery for 5 or more seconds. The only exception is the #1 error code (Oxygen sensor bad) since that code is always set by the ECU when you first start the engine... until the exhaust heats the O2 sensor considerably the sensor doesn't function. So you end up with error code #1 for about 2 to 5 minutes of driving typically, then it goes away. None of the other error codes reset though... ya gotta do it yourself by disconnecting the battery. mike c. Needless to say, there was nothing wrong with MAS. Quote Link to comment Share on other sites More sharing options...
dirtydevin Posted December 21, 2011 Author Report Share Posted December 21, 2011 Ok so it is likely that my cars low almost stalling idle set the mas code, as I had reset the codes prior to this drive. That makes sense, and I believe once I figure the idle problem out I should be running as good as I am going to until I get the maft setup and tune for all the cfm and boost from my turbo. Quote Link to comment Share on other sites More sharing options...
Spooled_Starion Posted December 21, 2011 Report Share Posted December 21, 2011 How does your air intake hose look? Could be a possibility your sucking in unmetered air causing lumpy idle and lean driving conditions. Check for cracks and vacuum leaks! Quote Link to comment Share on other sites More sharing options...
traps Posted December 21, 2011 Report Share Posted December 21, 2011 (edited) Thats peculiar because after rebuilding my turbo my car ran like crap.......then realized the MAS wasn't plugged in. So why did it start and why was I able to drive weird. Gremilins beware... To Mr. Devil, Spooled has a good point about vac leaks....are all lines Kosher? Sounds like your are slowly eliminating your issues. I am curious to see how it would run with a stocker on it. Did you say ya had an aftermarket boost gauge. And you said it was gapped at .32 did you play with larger gaps yet? Edited December 22, 2011 by traps Quote Link to comment Share on other sites More sharing options...
dirtydevin Posted December 23, 2011 Author Report Share Posted December 23, 2011 I have been through all the vacuum lines, and I don't have the factory accordian hose. I have a mandrel bend with couplers to turbo and stock mas and air box. Right now I have the factory style plugs at the factory gap 044. I am on the stock boost guage right now, but finding out everyone says they are not so accurate so I will be changing that out sooner than later. Quote Link to comment Share on other sites More sharing options...
Indiana Posted December 23, 2011 Report Share Posted December 23, 2011 I should be running as good as I am going to until I get the maft setup and tune for all the cfm and boost from my turbo.Did you max out the air fuel ratio on the turbo you have now? Don't be sold on a MAFT idea until you fix this for you can forget about trying to make it run afterwards. There's way to many new members on here right now posting possible solutions that are just wrong and way exagerated. There's hardly any older experienced members posting at all. With the economy and the holidays and the constant bickering back and forth most just said tough crap let them fix their own cars and just in the past few weeks I've seen some crazy examples of what is suggested others should do. There's just only so many times people will put up with having to justify their responses then they just won't make any. Unless you have at least an 18G or want to run a big16g at 25psi there's not one single reason why you need or would want a MAFT setup. There's something else wrong with your setup and it might be the wrong injectors or maybe its a mechanical issue with the valve train. Weren't you using that ruined MAF that someone hacked out the honeycomb from the end? You can't pay any attention to the way that car ran with that hooked up. Sometimes the car with run with the MAF unpluged and the ECU uses the tach signal as its the only input sensor it can use but it runs like total crap. You are a newer member and not familiar with the fuel system and how it responds so jumping into a fuel translator right now would be a big mistake. You can't even get your car to idle and there's no boost at idle and it won't matter what turbo you have. Quote Link to comment Share on other sites More sharing options...
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