br549,

You sure your intake gaskets are not leaking? This will also cause your issues.

Just because you have a certain code....fixing that item in the code.....does not always fix the problem.

Might be what I mentioned earlier.....wiring harness issue somewhere.......these damn things are old as dirt.

 

Stilealive, thanks for the reply. I'll spray some brake cleaner on the intake tomorrow and see if that changes anything. I think the first MAP sensor I put on did get messed up from me soaking the intake in soapy water. When I took the intake back off because of the map sensor code, I pulled it out and it was wet inside of the part it plugs into. Also the TCS and ABS turned off automatically, they did that when the map got unplugged a couple of years ago. Thanks for help,

 

When I broke the wire on the oil pressure sensor, I bought another plug and wired it in. The gauge works backwards now! When I turn the key on, not starting it, the oil pressure gauge on the dash pegs out, but when the car starts it flies back to zero, I wonder if the teflon tape I put on the threads is causing that issue?

 

I'm not going to address that clown anymore in this thread, stay hurt over a disagreement.

Look at your pressure readings still, they never changed man. That is 1 of 2 things, the MAP reading is bad still or you have a giant intake leak and the MAP is correct. Even with pretty bad intake leak that pressure should have change even 1 or 2 kPa but it didn't it stayed rock solid at 94 that's not normal and indicates a bad MAP reading or sensor.

I never said replace the MAP and you're good I said to check it first and the wiring, the MAP sensor may be good but the signal return may be messed up back to the PCM. I actually tune my cars and 100% for a fact your fueling is dependent on your pressure reading from the MAP. I'll post the VE table to prove it.



Notice this table is RPM vs MAP not anything else. For your car to run smooth ever again you have to get that MAP pressure reading actually working. This is my VE table and I'm cammed and modified but you can see the difference in the fueling values in the cells, this is how fueling is calculated. So looking at this and your 94 kPa reading at best your RPM was at 410 which puts your fueling value here at 62 which is CRAZY rich for idle, enough to stumble, backfire, and smell pig rich. As I said I have a cammed car that doesn't hold as much vacuum but I maintain a 55 kPa, at that same 410 RPM fueling would be at 28 LESS THAN HALF FUELING. If your reading never changes from that 94 your going to stay in that row through the entire RPM range and wash down your pistons and cylinders, do that long enough you'll gas foul the oil and thin it out so much it'll spin a bearing from loosing viscosity.

 

1987firechicken thanks again for taking the time to help me. At this point I'm not really sure what to do next. What should I do next?

 

I'll start looking for vacuum leaks. I'll spray the intake down with brake cleaner and see if it changes anything.

 

I think you need to test that MAP per the youtube video I linked up above there, the guy is very clear and concise and tells you what the reading should be. I think you should Ohm out the sensor (the way he describes in the video) and make sure it's good first but you'll have to get it out of the intake unfortunately. Here is the diagram for the MAP circuit and connector match them up to what he talks about in the video.

 

As soon as this rainstorm passes I'll go out there and pull it back out. I can pull it out without removing the intake, I just pop up one side of the fuel rail. I checked the voltage on the plug, but not the sensor before I put it in. As soon as I get the results i'll post it here. Thanks

 

Spraying brake cleaner into a vacuum leak is the same as dumping more fuel into the cylinders you're not going to really find anything like that without it idling better than 400 RPM, you won't know if it died from the extra brake clean or because it already doesn't hold idle.

This really doesn't act like a leak, a minor vac leak should make your car run leaner and idle a bit higher and it would take a hell of a vac leak to make it completely die. I've seen people take off the brake booster hose and it keeps running and that's a pretty massive vacuum leak. Your reading doesn't budge at all from not running to 400 RPM, it should have twitched if you have any vacuum at all. I guess you could check and see if you do have a vacuum by pulling and intake hose and feeling for suction. Your MAF airflow certainly thinks that air is being sucked past it so I'm betting you do.

 

Okay, I'll go check the intake hose. If the maf housing was installed backwards could that cause that reading? I gotta wait till it stops raining or slacks up a little.

 

No MAF and MAP are not linked, and in fact your MAF grams per second looks pretty good to me. A general rule of thumb is your MAF reading should be in the area of your engine size in liters so around 5.7ish which is what you are seeing. Also I can tell you have some form of vacuum as air is flowing past that sensor and you have that reading, air does not move past it unless it is blown or sucked past it, in this case it would have to be sucked past it via a vacuum.

That alone tells me that your MAP reading should have changed and it means that your intake is sealed up enough to pull air through the filter and past the MAF. You may still have a vac leak but you have to get that MAP reading moving before I would go looking for one.

 

Well. if anybody out there has to remove your MAP sensor, go ahead and spend the extra time to remove the intake first, or you may end up doing what I just did and break it off in the manifold. 1987firechicken sorry I didn't get a chance to test MAP sensor # 2 for you. I will test # 3 for you before installing it. after I pulled the manifold I was looking at the oil pressure sensor, and it was melted around the connector pins. I guess I'll fix that too while the manifold is out!!

 

Well before you replace the MAP go ahead and check the voltage for the MAP on your scan tool with it entirely unplugged. Obviously that should report 0 volts but if you have a reading then you'll know you have a wire issue somewhere to the sensor.

If you can't get it from the scan tool you have you'll have to check it on pin 32 on your PCM's blue connector from the wiring diagram I posted earlier.

 

Just back in from working on the car with my brother. We got the intake back on, got the new oil pressure and map sensor on without damaging it, everything is going well! I tried to start it and it was doing the same as it was before. He pumped some gas out of the fuel rail and it was solid white! My battery went dead before I could get it all out and I don't have a battery charger so I'll finish pumping out the tank tomorrow. when it died on me I had just filled up at the gas station and made it about a half mile when it shut off. there was another car sitting there where I coasted too that was waiting on a wrecker too. Tomorrow might be the day!!!! I'll report back tomorrow.

 

Are you saying this fuel was put in and thats when all your issues started happening....?

You never mentioned this gas fill up issue.....

 

wow so it started happening right after fill up? Should have checked that long ago lol.

Pics of the gas please.

 

Thank everyone for helping me, it was bad gas. I pumped out the bad gas and put new in it and it started right up but then started missing and making a loud random knocking noise. When I pulled the # 1 spark plug it was wet and mashed closed. I'm going to get a camera on a stick tomorrow to inspect the damage.

 

Your welcome. Good to hear you found the issue.

Just remember, list all negative events that you experience so we can help you out better. If you mentioned stalling out right after filling up, I'm sure everyone here would call...."Bad Gas".....

Also......please.....DO NOT trust the PCM......as you now see your PCM is one of those that DOES NOT play nice, like mine is. It will show you false codes (MAP Sensor) because some PCMs get confused. Some are rock solid. You can't/shouldn't always just replace the items shown in the codes.

Even a veteran member.......1987firechicken......has been taught something about PCMs that he never knew.....PCMs are NOT all created equal. firechicken was having you chase wiring diagrams and voltage checks...LOL...not even close.

 

stilealive, Thanks for helping me through this I appreciate it. I'll be pulling the motor in the next day or two so I can take it to a machine shop to be rebuilt. The way it sounds, it probably has a broken rod. The # 1 spark plug was wet and was mashed down to the electrode. It has a loud random knock that's the only way I can explain it

 

Oh man....sorry to hear it. Well it’ll come back better than before.

If it’s in the budget.....get a new complete engine wiring harness. This will help in the future ruling out bad/old/worn wiring and connectors as part of an issue. .......If the budget allows.

At least go through the old harness really well and repair or strengthen any worn areas.

Do you plan any performance upgrades during the rebuild?