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Discussion Starter #1
My other thread was about getting this car running. Now that it does start and run, it doesn't do so very well. The car will start with one or two tries. Sometimes it fires instantly, sometimes it takes a bit of cranking. It is running very poorly. The idle is very erratic (rev, rev, rev, rev) and shakes the engine quite a bit. However occasionally it levels out. Changed the MAP sensor, and it wont even start with the new one, which really boggles me. With the old one the idle is erratic, and giving it any gas pretty much stalls it. With the MAP disconnected, it revs up really high and then stalls. The exhaust smell is extremely strong, seems like the fuel mixture is all wrong. I have also replaced all the plugs (old plugs were completely black from the threads down), wires, coil, and cap. I suspect my coolant temp sensor needs replacing, as the fan wont turn on until I unplug the sensor. Would this cause an erratic idle?

Only codes, 12, 13, 22. All related to things I had unplugged or messed with already, I believe.
 

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Is the new MAP an OEM part? It doesn't necessarily have to be Mopar. I have had issues with aftermarket/universal/generic replacements. It may be running rich warm and cold?
An OEM O2 sensor can also be an important consideration.
If the old plugs were carbon fouled, the new ones may be fouled now also if it is rich. I have a small sandblaster for cleaning fouled plugs that aren't worn out. A wire brush cleaning might work.
Are they the correct Champion Copper Plus RN12YC spark plugs?
Is the injector spraying a nice, light conical pattern and not just dribbling and streaming? An advance timing light can be used to view the injector pattern.
 

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Discussion Starter #3
It's a MAP from Oreilly. Seems like parts at stores a few and far between in stock for these cars so I went and got that one. Perhaps I should get an OEM online. The plugs are not Champion. I noticed when I pulled the old ones they were. I did gap the new ones to .035. Are you able to see the injector with the light by aiming it down the throttle body?
 

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Did you change the ignition rotor? That can cause huge problems and failure to start.
Check the sensor ground cable, which is at the driver's rear corner of the block, a large ring tongue terminal. The harness was made with no slack, and sometimes the strands of wire break and the connection looks intact, but isn't.
Have you run a new tank of gas through? If not, how old is the gas? Have you changed the fuel filter?
Also, examine very closely the entire vacuum harness, both the rigid tubes and the rubber hoses. Very easy to snap them, they get brittle; or they crack and you may not realize it. Make sure they are all connected properly.
 

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Discussion Starter #5
Rotor is new. Fuel is new. Filter is new.

I'll check that strap and the vac lines today.
 

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You should be able to Google a brand name and part number to see if the MAP sensor is advertised as OEM or not. I have seen 'OEM-style' in the description of some aftermarket parts which gives me cause to question whether they are applicable to my car or not.
Non-OEM parts can cause issues that are the same or different than what you started with. It can waste time and make you doubt your diagnosis when you actually were right all along.
Have you looked at the new plug tips yet? I have had problems with platinum spark plugs in these cars, particularly Bosch. Autolites and Motorcrafts as well. FYI, some people have not had problems with different plugs, but I have.
You should see a nice injector spray pattern in subdued light with the timing light aimed at the base of the injector. Adjust the timing light advance control until the inverted cone shape of fuel mist appears.
 

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Discussion Starter #7
You guys rock. Gives me a lot to work with for the weekend. The plugs are autolites.
 

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Every Autolite I have ever used in any car has given a slightly rough idle, even when new, and has also flashed over the insulation, even with new plug wires. Champions are the way to go; although that can't be responsible for running this badly.
 

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Discussion Starter #9 (Edited)
It ran better with the carbon fouled Champions. The idle is very specific. Revs consistently about once per second. And dies with throttle. Anyway thanks again lots to look into this weekend.
 

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Anyway the guy who did my fuel pump was messing with lines at the TBI and had them crossed.
Chances are fairly good that he screwed something up somewhere else or hit something and broke it. There's no reason to even remove the fuel lines at the TB to do a fuel pump; the pumps are self-priming and any air in the system would get pushed out fairly quickly by either the pump's own fuel line priming cycle or by normal flow when attempting to start the car. Even if you take the lines off, it's very hard to put them back on wrong because they tend to stay in their positions. I would look for things connected to the wrong ports and cracked hard plastic. There should be a label under the hood somewhere with the vacuum routing.

(I'm not trying to be harsh if YOU were the guy who did the fuel pump... there's a difference between learning on your own stuff versus learning on someone else's under the pretense of repairing it. I replaced a fuel pump once because I didn't check the electrical connector feeding it. Chalk it up to experience. But I would be upset if this was a shadetree mechanic, or worse, a shop, that "fixed" my car like this)
 
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I once reversed the return line and the vent line to the fuel pump when replacing a tank, because they are both 1/4" hose and right next to each other, and I had not labeled them. Pump buzzed loudly and gas tank gave a "whoosh" when I took the cap off. Luckily I only ran it a few minutes before I found my mistake and fixed it.

Look also for a leaky gasket at the bottom of the throttle body, or loose bolts holding the throttle body down. They torque to about 17 ft-lb, as I recall (200 in-lbs).
 

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Discussion Starter #12
He was a former friend that I used to work with. Not at all friends anymore. Had a side business going repairing cars. I am quite a novice about cars and I was also surprised he would take the lines off the throttle body when he changed the pump. Didn't make sense to me.
 

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No, there's no reason to do that. And the lines have copper crush washers at the throttle body, so you can probably get away with it once, but they should be replaced after that.
 

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The fuel lines screw onto the throttle body with big hex fittings, and they use a thin copper washer to make the seal between the fitting and the throttle body. As you tighten the fitting, you compress/crush the washer. Technically, you are not supposed to re-use those washers, but in practice, I found it did not leak when re-using them one time.

This is my article on removing and cleaning the throttle body on a 93 Daytona:
Rebuilding the Chrysler-Plymouth-Dodge 2.2 - 2.5 Engines’ Throttle Body
 

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What, very conceivably, could have happened, especially if he also changed the vacuum lines, is that you have ported vacuum to the MAP sensor now instead of manifold. That's going to cause it to see atmospheric (WOT) all the time when the throttle is closed and then increasing vacuum as ir is opened, exactly the reverse of what it should. If you look at Bob's article, there are two fittings, one on the front and one on the back, that are about the same diameter. The difference is that the one on the back is ported versus manifold vacuum on the front. If the MAP is on the firewall or strut tower, like it was on my Spirit, it "looks like" the MAP should go on the on on the BACK when you've ripped everything out and can't be bothered to read the little tag at eye level above the motor or go look it up.
 
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Discussion Starter #17 (Edited)
Not much progress today. I pulled the auto lite plugs and they were dry fouled. Keep in mind the car has run for a total of maybe 5 minutes since they were installed. I installed champion copper plus plugs. I started working on the CTS but the thing is VERY stuck inside the water box. It won't budge. I did plug up the new one without taking the old one out to see if there was any change in idle. It seemed moderately better. I was going to through a lot of what you guys posted for me (checking for vac leaks, checking injector spray pattern, etc) but it won't start running for more than 30 seconds and its struggling the whole time. Definitely sounds like it has a miss and definitely seems to be running rich. When I start it, it will rev really high then come back down and die. Oh also the vac line to the MAP connects to the front passenger side on the front of the TB. I don't get it...car was working better a week ago....it would idle decently well. Enough to move up and down the driveway. Now it won't even stay running.
 

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Try PB Blaster on the CTS. I've seen it work miracles on nonferrous parts. A lot of the stuff on the can I think is advertising smoke but their product does seem to work better than others, to me at least. The key to any penetrating oil is soak time.

You might try measuring the resistance of the old and new CTS's. It should be about it 9-10kohm at ~77 degrees. If both sensors are at the same temperature and have been for a while, the resistances should be close. A falsely high internal resistance would make the engine controller think the engine is extremely cold all the time, since the resistance of the CTS decreases as its temperature increases.
 

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I would not take the CTS out. They rarely fail. Measure the resistance as B10alia says. With cold engine in this climate, should be about 11K to 13K ohms, and will rapidly decrease if you can get the engine to run long enough to get warm. Still best to check vacuum lines and that ground. Some of the vacuum lines are in that plastic sleeve on the back of the valve cover and hard to check. But make sure every single vacuum line is connected to the proper port.
 

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Discussion Starter #20
Has anyone got a vacuum diagram for a non turbo? Turbo is all I can find in a Google search. And Bob can you describe where exactly the ground wire is?

I appreciate you guys so much.
 
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