Progress..finally....(I'm slow I guess)

[Pick]

OK, tonight I finally took the time to put the carb back together after getting a new TPS....it's almost right......but ya know the pesky little rod that runs from the choke down inside the carb? well.....on my third time putting the top of the carb back on, it decided to come unhooked at the bottom and I didn't notice it until I had all 13 or 14 or 56 (!) bolts back in the top of the carb (again, for the third time.) (I'm an idiot.)

The car runs now without billowing black smoke, and even seems to idle smoother, but I know I'm not done yet. I just didn't feel like hooking the scan tool back up to prove to myself that I still have more work to do.......did mention that I had to put the top on the carb THREE TIMES?!?!?! (sorry.......I'm a bit testy at the moment.)

OK......it runs, it didn't poor fuel all over the engine compartment, burst into flames, and I could hear the turbo spool (some) when I took it for a test drive down the cul de sac without the air cleaner assembly......so I'm closer. (but I could also hear that I have cracked header(s).....I suspected it before, but it's a fact, at least on the driver's side.) Still no brute acceleration, no sign (or sound) of the 4-barrell opening, and very little gee-whiz factor.

I'll report back when I do another scan and see what's next in line to be replaced.

BTW, Pat, did you shorten the pipe on the Civic cold air intake? I got it in there without modifying it, but I'm thinkin' that shortening it at least an inch on the long side would make it fit more neatly. The upside of the whole evening is that my Civic air intake came with a nice yellow silicone boot instead of the blue one it showed in the picture......it looks nice with the yellow and orange "6" decal on the chrome carb elbow. Again, I'll report back if I break out the hacksaw. (and thanks again for the tip!)

I'm a tired idiot. and I still have to take the top off of the carb AGAIN eventually.........<sigh>.

 

[pat83t]

civic intake.

Nope mine fit right in without a single cut. Did you get the 92-95 air intake or the 98 and newer? I went with the 92-95 and that way only had to cap the one port. Also you will need a standard pcv push-in breather like you would use on a small block chevy valve cover and a push in breather oil cap. Glad to hear that me getting bored at work one day really helped somebody out. People kept asking me why I didn't just market them and make a few bucks but the way I see it, it is hard enough to find performance parts for the carb'd turbos and if I share the info with others maybe they have just as good idea or better that they are willing to share with me sometime.

 

[Pick]

I used the same part number you suggested. I got it installed last night but it just seemed a bit tight. (of course, it might have to do with the fact that I wasn't a real happy camper by the time I decided to try it.)

 

[pat83t]

Yeah that might have something to do with it. The biggest frustration for me was getting the silicone boot onto the carb bonnet, everything else was pretty easy. Did you remove the mounting brace for the stock air box? I yarded mine. There is a little brace that comes with the kit and there is a hole on the inner fender right there that makes a real good spot to attach it to. I could have cut mine down but the further forward it is, the further away from the motor it is and the more it is shielded by the radiator fan shroud from getting hot air off the radiator.

 

[Pick]

Good points!

Yes, I removed all of the original air cleaner assembly and support bracket as well. (fortunately, I had already polished the carb bonnet and slid the silicone boot over it the day before my carb fiasco or things might have gotten UGLY.) Now that it's in and you pointed out a couple of benefits that I hadn't thought through, I'll probably leave it the way it is.

Tonight I chased down vacuum leaks and tried to find a MAP sensor at local parts stores with no luck. (I checked the hose running to the MAP sensor and it wasn't leaking, so I'm assuming that the MAP sensor really is dead.)

One step at a time......

 

[pat83t]

Did that kick on your check engine light? just wondering because I am not real sure about mine? Some cars it does other cars it doesn't.

 

[Pick]

My check engine light has been on since the day I bought my car. This is the first year that it failed emissions though, so I'm just now chasing down all of the possible reasons for it. I'm guessing that the TPS failure was the last straw that lead to the emissions failure, but it is just a guess.

As soon as I can get a MAP sensor, I'll pay attention to whether the check engine light finally goes out or not. (even with all of the stuff I've found already with the MacLogic scan tool, it still wasn't throwing any codes using the paper-clip trick.)

 

[Ttype83]

Originally posted by Pick
As soon as I can get a MAP sensor, I'll pay attention to whether the check engine light finally goes out or not. (even with all of the stuff I've found already with the MacLogic scan tool, it still wasn't throwing any codes using the paper-clip trick.)

Glad to see that you are gaining ground , I had to pull the carb cover off 6 times before I got it right. (Wife had to help)

You can test the MAP by unpluging the vac hose and pluging it. Attach a new hose to it and start the car (make sure it is warmed up first) Now suck on the hose, you should hear the idle change.
Jim...

 

[Pick]

Jim, I had to do it solo.........I'm sure that contributed to my frustration.......the MAP sensor is (was) undoubtedly the original, and surprisingly enough, the hose leading to it was intact. (I can't say the same for some of the other hoses, however.)

I have a few caps in places that I don't figure they should be.......and even with a diagram, I can't figure out where they were supposed to go.

 

[Pick]

Still confused....

OK, new MAP sensor is in place, but it is still reading the same as barometric pressure (29 iHg) and doesn't change, even putting the engine under a load against the brakes. I retraced the line and didn't find any splits. The screwy thing is that it actually ran smoother, although the idle was a bit high. (and I don't get any puffs of black smoke anymore......I did once in awhile yesterday.)

Oh......and now the car is throwing a code 55. (bad O2 sensor....somehow I knew that was coming.) Once again I'm confused though, because the O2 cross and rich/lean indications were changing after various throttle blips like I would have expected. (the O2 cross ranged from 0 to as high as 22.)

And Pat, yes, my Check Engine did go off after I installed the MAP sensor.......go figure.

Am I missing something?

 

[b4black]

If your check light is out, then there code may be a old problem. Only when the light is lite, there is something wrong. Try disconnecting the battery for 30 seconds and clear the codes. Then see if any come back.

Did the new MAP have an orange key for the connector to plug into?

The orange keyed MAP sensor is a 2 bar sensor, meaning it can see about 1 bar (16 psi) of boost and 1 bar of vacuum. The blue keyed BARO sensor only see one bar vacuum.

With the engine idleing, disconnect the MAP line and see if there is vacuum at it. There should be. A vacuum/boost gauge would help in this case, cause you would know what the manifold pressure really is.

 

[Pick]

The new MAP matched up with the A, B and C indications on the connector........and it is orange inside......it is NAPA #2-1962, if that helps any. But, now that you brought it up, one of the keys in the MAP didn't match the slot on the connector for the same "hole" on the Regal. (there are three.) Externally, the old one and the new one were identical, however. (yes......I know that doesn't mean much.)

I guess I'll have to disconnect the battery to clear the codes tomorrow, and see if I have vacuum at the MAP sensor.........and see if it gets me closer.

Again I offer a HUGE THANK YOU to Rich, Jim, Pat, and anyone else that reads this mess for that matter, for the support and information. At this point, a place to vent is more than I could ask for........having helpful feedback is HUGELY appreciated!

 

[b4black]

Re: Still confused....

Originally posted by Pick
OK, new MAP sensor is in place, but it is still reading the same as barometric pressure (29 iHg) and doesn't change,

Originally posted by b4black
The orange keyed MAP sensor is a 2 bar sensor, meaning it can see about 1 bar (16 psi) of boost and 1 bar of vacuum. The blue keyed BARO sensor only see one bar vacuum.

OK, I thought about this more and these two statements don't fit together. On a NA engine, the MAP and BARO are actually two sensors, but the are the same. Both are 1 bar, blue units. With the engine off, the will read the same. (The BARO is located near the ECM and has no hose connected to it).

On a turbo V6, they will not read the same. 0 vacuum is full scale on the NA MAP and BARO, but mid scale on the Turbo MAP. This is becuase the Turbo MAP needs to go above 0 vacuum (aka boost).

(I'm on a roll )


With my scan tool I get
BARO: 100 kPa or 4.70 V (full scale)
MAP Off: 52 kPA or 2.34 V MAP idle: 26 kPa or 0.68 V
MAP 2 psi: 62 kPa or 2.70 V
(The MAP at 15 psi would be full scale 100 kPA or 5.00 V)

BARO and MAP off are same ambient air pressure, but different scale, so the Turbo V6 scale is off by a factor of two, because it's a 2 bar (or 200 kPa or 59 inHg) scale. 52 X 2 =~100.



Your 29 inHG (inches of Mercury) is about 100 kPa which is about ambient pressure, so your BARO reading seems right.

The 29inHg MAP is when? Idle or off or ? Can your scan tool display Volts?

29 inHg on a Turbo MAP is full scale or what I'd expect at 15 psi of boost, BUT I suspect your scan tool, unlike mine, is correcting for the factor of two., so it would be correct with the engine off. If you apply pressue to the MAP, it should go above 29 inHg.

(I am getting carried away? I hope I'm explainging this well enough that it's understandable)

So BARO 29 inHG is right. The MAP 29 inHg OFF would be correct if your tool corrects for the 2 bar scale. Then it must be a vacuum problem or BIG LEAK. If it's not a line, then check the wastegate actuator or boost light swicth.

 

[Pick]

Thanks Rich!

Actually, that did make sense. (should I be frightened?)

The MAP reading didn't change with the car on or off, it is still 29 iHg. My scan tool does read volts, but I don't remember what the reading was.......I do know that the MAP volts didn't change either though.

I guess the good news is that the new TPS actually worked.......right now the idle voltage is reading 1.00........

I haven't messed with it since my first post last night, but hopefully I'll be able to this weekend. I have found quite a few leaks, so it is definitely possible that there are more that I haven't found.

Thanks for your help!

 

[Pick]

OK....tonight I disconnected the battery to purge the computer of all of its previously learned ills and codes, then ran the MacLogic through its paces again. MAP is still reading identical to atmospheric pressure and the MAP voltage is staying constant at 4.8 volts. Everything else appeared to be functioning normal including the O2 sensor and it didn't throw any codes on the initial run-up and warm-up, so.............I tried a quick spool-up and launch in front of the house.

In gear, left foot on the brake, gas easing down until it "felt right" ........I sidestepped the brake and it launched a few feet .......and then it spun the right rear as the turbo spooled up (I'm thinkin' "WOW, it's never even done that on wet pavement! KEWL! This is more like it!") the car grabbed second and pulled........and then it absolutely fell on its face and spewed black smoke like a diesel. (LOTS of black smoke) My neighbor was leaning on his '69 Camaro watching and was really impressed right up until it did the Kenworth impression. According to my neighbor the black smoke started just before the car went flat and then just got really ugly. (Barry asked me what the metallic clanking noises were too.)

It took letting off and letting the unburned fuel all get pumped out through the exhaust before the car recovered enough to give it any gas at all as I turned around and limped back to the house feeling totally frustrated yet slightly more motivated to see what it will do if I finally get it right. (at partial throttle and "normal" acceleration it did fine.)

Now that I'm beyond the realm of what the MacLogic can help me with (aside from the MAP sensor issue)........this one has me scratching my head.

Why would it start out VERY good then all of a sudden go WAY BAD midway through second gear?

 

[Peter]

Originally posted by Pick
MAP is still reading identical to atmospheric pressure and the MAP voltage is staying constant at 4.8 volts

You have to get the MAP working. The reason for the black smoke is that the MAP is telling the computer that the engine is running at full boost when it is not. [ 4.8 volts].

When I was working on my boost retard control I did a calibration on a 2 bar MAP sensor, and found it to be completely linear, with some deviation allowance for measurement accuracy. I found that 0Hg/0psi [Atmospheric] to be 2.375 volts, and 25Hg on a vacuum gauge to be 0.218 volts. These numbers will vary slightly with atmospheric pressure and with each individual unit. However they are certainly good ballpark.

If you are measuring 4.8 volts at the output of the MAP when the engine is not running, and it never changes when the engine is running, there is either a problem with the wiring or the sensor its self.

Try this. [I do not know your car and cannot be specific about which wires these are. Maybe someone else can help with specific wire colours.]

Disconnect the MAP sensor. At its connector measure the following, with the ignition on and engine not running. [Use a good multimeter with high input impeadance, not a cheapy car type meter.]

AT CONNECTOR

A = Ground
C = About 5 volts.
B = May be infinite or some varying voltage. [Do not measure this if you do not have a high impeadance meter.]

If you get these readings then the wiring and computer are probably OK.

Turn off the ignition and reconnect the MAP.

Repeat these measurements. [Piercing the wires with a pin is not recommended but you may have no other choice at this point. Re-seal the wires with silicon when you are finished.]

The readings should now be;

A = Ground
C = About 5 volts.
B = About 2.4 volts

If the ‘B’ [ the MAP return voltage] voltage insists on staying at 4.8 volts there must me an internal problem in the MAP.

Doing this will throw code in the computer which you will have to clear when you are finished.

 

[Pick]

Thanks Peter. That information will definitely help me isolate the problem(s) with the MAP sensor if it comes down to that.

After reading your post, and thinking back to Jim and Rich's, I pulled the hose and the electrical connector from the MAP sensor to check the voltage......but when I went ahead and started the car, I got nothing.....no vacuum, no pressure, nothing at the hose......nada. So, even though the line looks good, apparently there is something else amiss in the line or in the wastegate actuator. (gee, I'm quick huh?)

I ended up trying to break my thumb while horsing around with my boys shortly after that, so I'll have to get back to checking it out when I have two working thumbs again. (or have 10 working thumbs instead of 9 perhaps?)

I really do appreciate, and really do try to listen to the answers to my dumb questions!