MAF Problems Got Worse Would Love Help!!

Hello!

I'm new to the forum and could really use some help, I recently inherited a 87 200sx and loved the thing to death. I have been driving it daily for 2 months until I mucked it up.

It started with my car having some fuel efficiency problems.  The car had a strong smell of gas wile running and black "soot" coating everything from inside the air box to the tailpipe. I thought my maf sensor may be coated in this soot and causing a inaccurate reading. I disassembled everything and it was caked on one side of the sensor so I cleaned it with CRC mass air flow cleaner. Put everything back together and it would only rev to around 2000rpm. From what I could find out seemed like a safety mode after reading a little bit decided to disconnect the battery and leave it for awhile. I disassembled everything again to double check everything was ok and it seemed fine so I reassembled and then connected the battery it ran very rough still wouldn't go over around 2000rpm. It died shortly after and will not start again just keeps cranking like it wants to go. What I thought would be a simple job turned into a job that I'm now in over my head.  :sniffles:

I'm assuming with all the "soot" it had a issues before hand.

I am by no means any type of mechanic and have limited knowledge.

I have a love for this car and would GEATLY appreciate some help or ideas

What motor? Stock?

CA18ET 1.8 turbo SGL manual trans roughly 130,000km and its so stock it hurts

seems I may have posted this in the wrong section ooops don't know if I can move this I'm rather handicapped at this.

It should start with a bad air meter. You need to figure out why it not starting; fuel, spark, and compression. The spark needs to be at close to the right time in reference to the engine. If I remember correctly, ca18et's dizzy is set strait at zero at tdc and the ecu handles the timing.

Once you get it running, even like crap, run through the codes. See what it says. I suggest buying a multimeter and an FSM; if you want to keep the car, you'll need both. The code system lacks a little on ignition, but just keep plugging with the multi and remember what it needs to work; typically they're rewarding cars if your patient, willing to learn, and don't mind digging in.

Good luck.

Thank you for the help I will take your advise an see what I can get done tonight.

If you don't have a FSM yet, shop EBay - can usually find one for $30 or less

Believe it or not this is one of the cleanest ones. Putting new plugs in shortly. Does anyone know where all this build up is coming from because like I said it coats pretty much everything.

WAY too much fuel! It is flooding the engine, and as you said you can smell it.  Have you checked the codes on the ECU (engine Control Unit mounted near your left foot)? It can help lead you to what ails it.

May be a bad coil. Could be just running on the Less optimal bank of plugs. Go for the codes first - it's free.

So I've got new plugs in it do I try and start it or wait to get the codes.
About the ecu so I have to dismount the whole thing to get to the diagnosis mode screw cuz I can't seem to reach it.

I know next to nothing but trying to pick up as much as I can wile I go.

You guy have been very helpful so far thank you!!

There's just two screws or 10mm bolts holding the ecu up. The top half of the ecu clips in, just the bolts/screws at the bottom. You'll need to unmount it and rotate it down with leaving the harnesses connected. From there you can still run the car, get to the code position screw, and run codes. You'll be running codes with it running.

The process should be (in the book) something like check a few codes, start the car, check a few more, etc.

Do you have the FSM? I think the newest I have is 86 model year.

I am currently checking codes but what it's displaying is haveing nothing to do with what's in the book. 
But it starts now!!!

Is it bad i don't know what FSM is ? The service manual?

Factory Service Manual. You will learn the acronyms soon enough. Some ECU's have all the codes on the cover, if not you can find FSM's in this forum that got uploaded, nice in a pinch. But as Red said, you should be able to score one on ebay that fits your car.

I have the FSM and have been using it but the codes I saw dont really match up with what's in the book
Two codes don't exist that I pulled and the other three say:
 fuel pump ( I could believe with the amount of fuel on plugs)
the crank angle sensor
And the it says ecu operating properly

And on the ecu the sticker says 92 does that mean is at 92 ecu or it is the 92nd car to come out

Still guys thanks so much!

One of the turbo ecu I have here also says "92" on it. It's from an 85 I think. It also lists the codes on the ecu itself.

If the crank angle sensor is going out you can be having some running issues for sure. The pickup goes out, they can be found for around $100 if I recall correctly. Check the wiring for the dizzy, there is a connector at the dizzy and one inline about a foot away for the crank sensor.

So I have got the crank angle sensor out. I have checked the harness its got power going to it. Should I order a new sensor and hope for the best? or is there a way of testing the sensor? It seems like it is my problem just by the effects a bad sensor could have it matches up pretty well with whats going on with the car.

I found a small vacuum leak today this wouldn't cause all of the right???  :cantlook:

Does anyone know if the V-6 sensor will work(the one I link to below) the only other one I can find at the moment that says its for my specific car is $200 bucks

http://store.acadianasportscars.com/en056-0004

that's the other one I was looking at buy the Canadian exchange rate sucks right now but ill order it and hopefully that's my problem.

Hope that will fix some of your issues. I replaced mine twice over the years I have had my CA18ET, fixed it right up.

well got the new sensor in today and didn't do a thing
I'm at a loss dunno what to do now

Is it running, but with too much fuel? Sounds like a familiar issue with a bad temperature sensor, but could also be the IAC device (think that's what it is called). That thing is in front of the throttle area on the passenger side. It looks a bit like an ice cream cone , has some hoses going to it as well as a plug. It has an internal heater that comes on when you start. This heats a bimetallic strip that twists as it heats, the twisting opens up an air passage that leans out the mixture as the engine warms, maybe this is stuck? The idle air adjustment is also available to help lean the mixture at idle. On my 84 model it is mounted on top of the radiator and it is a simple bleed port. As you back the screw out, it allows more air to get in.
Sorry to hear the new sensor did not make any difference! Keep it handy, you will likely need it someday.

I will check that out today
As it sits right now its stuck in "safe mode" and just it seems like its running very rich

Damn, for such a good looking car that's a pain! When you reset the ECU codes, does it show any new codes? I wonder if the ECU is messing with you?

So it seems my waste gate is stuck. Anyone know if that would cause the rpm limiting

I don't want to take away from Cajun's help, but it sounds like the MAF may be bad.  I had an 85 that was doing the same things as yours and after replacing EVERYTHING, I finally did the MAF, and it never had run better.  The temp sensor is also a good possibility like Cajon said, but to me it gives all the tell tale signs of the MAF.  That's why everything is so rich and why it won't rev over 2K.  BTW, my ecu never threw any codes for the MAF.  Keep in mind the OBD system is quite crude in our cars.

Not revving past 2k is usually in my experience the maf. Do you have another you can test with? Or maybe someone close that would let you borrow there working maf just to see if it eliminates the problem? Last time I checked Oem-Surplus. com had a couple in stock you might want to grab one from them as it will be brand new.
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