Just got a Daytona, need some help with sensors

[spooled up]

Hey everyone. I recently got a 1988 Daytona Shelby in a trade for my Honda CRX. I dont know a thing about Dodge, so I'm hoping you folks can help me out.

There are a few issues with this car. It starts up and runs and I can drive it but it will not idle under 1500 RPMs. It will usualy fluctuate between 1500 and 2200. The thing also runs stupid rich. I'd say I only get around 200 kms to a tank. The two codes that it is throwing are 13 and 15. 13 is something to do with the MAP sensor and 15 is vehicle distance sensor. I have no idea what the previous owners have done to this car to try and get more performance out of it, but it is clear things have been played with.

heres the first thing that concerns me:

This sensor here here, sorry I dont know the name of it, has been tampered with like so:

The wires coming out of each side have been jumped together with another wire with a resistor on it. Like I say, I dont know what this sensor is/does but this may be the source of one of my problems?

The second thing is a sensor that I believe is on top of the transmission. It has been unplugged and the copper probes have been bent over:

Sorry, it was hard to get a good picture. Any info on what sensor this is?

Another thing I noticed is what looks to be a vac block or something near the right front headlight under the hood and another one near the first specified sensor which arent in use. I dont know what the purpose of these are but I doubt it has anything to do with my problems. Heres pics for refrence:




Catch can leaks a little bit too so I'll be fixing that.



Any help is appreciated folks. Like I said I'm brand new to Dodge so I hope I can learn from this site.

Steve

[lancerman23]

hey congrat's on getting an american classic car instead of the run of the mill japaneese product.

looks like they did a little trick to fool the map sensor when running higher boost. these cars are set from the factory at 12psi and any time you run higher then that you have to fool the map sensor, that little diod helps so the map sensor wont read the higher voltage, otherwise it will sputter, buck and snort at ya while your driving, wont hurt anything that i'm aware of, just really annoying when your trying to kick another honda's butt.
here is a link to a website that everbody goes off of to get these little tricks of the trade Donovan's Dodge Garage

tons of usefull knowledge there bud. if i were you i'd solder that diod on there better and cover it with electrical tape. Also those other vacuum blocks, one is for the wastegate and the other im sorry i dont remember what the other is right off the top of my head, but you should retrace all your vacuum lines and make sure that there all going to where there supposed to be... in my oppinion i think that's why you've got such bad idle, let me know if you need a vacuum diagrahm i got some i can send ya. anyway man welcome to the community and good luck..hope this helped.

[spooled up]

So is that the map sensor right there then? That cant be what everyone else does when they want to run higher boost right? I just dont like the mickey mouse aspect of it. I like everything to be clean. Thanks for your help anyways man, and I would for sure like like the vaccum diagrams if you could send em to me.

[dragbaron]

If they've installed a diode in the map sensor wiring(first pic), then they were/are running higher than 14.7lbs of boost. That means that they have/had larger than stock injectors installed. If they did this with the stock computer, and no AFPR, then that could be part of the poor fuel economy. Code 13 means that there is possibly a problem with the vacuum to the map sensor, check that red hose and anything that may tee off it. High idle usually means that there is a vacuum leak. Pic 3 is the reverse light switch on the trans. The two solenoids in pic 4 are for the wastegate and purge. They probably have a manual boost controller, so you don't need the wastegate one. The purge solenoid tied into the charcoal canister(pic 5), which is emission stuff that you can maybe get away without having(don't know how Canada is about removing emission equipment). Code 15 means the computer is not getting a signal from the speed sensor, is your speedometer working?

[mopar4ever]

well you come to the right place as far as finding turbo dodge help and info

[spooled up]

My spedo works sometimes and other times it does not. As for the solonoids yes it does have a manual boost controller so I guess that explains that. Also, since I live in Northern Ontrario we dont have emission testing or anything like that so I guess the one under the catch can dosnt matter either. There is an aftermarket boost gauge in the car but there must be a vac leak because it never reads anything other than like 2 lbs of boost. There is an AFPR on it as well, what should the gauge read when the car is idling? Thanks for the help so far.

[[X]treme R/T]

that thing in the second pic is a resistor, not a diode. i cant tell the color bands on it. take another pic of it and ill tell you what ohm rating it is and the %of tolerance on the resistor.

[NAJ]

Welcome To TD!!!!!
Your idle and running rich issues are probably related.
You probably have a vacuum leak or low manifold vacuum.
The vacuum lines on these cars are central so any leaks will cause Map voltage to increase and the controller see's this as increased airflow so it increases injector pulse width which with the additional air from the leak and the added fuel increases idle speed.
Verify engine vacuum is correct (16-20" HG).
Tee a vacuum gauge inline between the manifold and baro solenoid(the red line in your first pic), if correct make a new hose and tee the vacuum gauge between the baro solenoid and Map sensor, vacuum should read the same.
If vacuum is low check to be sure cam and ignition timing are correct.
Also since they soldered in the diode/resistor be sure that map voltage is = to vacuum pressure.
Backprobe the signal and signal return line at the map sensor connector with it connected and connect a digital voltmeter and you can read map output voltage.
The 2 wires are BK/LB and DG/RD.
They may not have cared about idle quality, only about loaded performance.
Also if the injectors are not stock is there an adjustable fuel pressure regulator, stock pressure could be too high for the injectors that are being used.
Also as someone mentioned the wastegate solenoid is not connected, what lines are running to the turbo?
I would start with basics and go from there.
The vehicle speed sensor issue could cause a high idle between shifts or stalling when coming to stop.

[spooled up]

Quote:

Originally Posted by [X]treme R/T that thing in the second pic is a resistor, not a diode. i cant tell the color bands on it. take another pic of it and ill tell you what ohm rating it is and the %of tolerance on the resistor.

Thanks man but I'm an electricain so I know all about that lol

I'll go out and get some pics of the lines that run to the turbo and all that so you can see what I've got.

[[X]treme R/T]

Quote:

Originally Posted by spooled up Thanks man but I'm an electricain so I know all about that lol I'll go out and get some pics of the lines that run to the turbo and all that so you can see what I've got.

whats the resistor value on it then? depending on the value, it could be resisting to much current or not enough and allowing the wrong signal to be sent to the computer. or just take a digital multimeter and check the actuall value. you said your an electrician so i dont have to go into detail on how to set up the multimeter or anything lol.

[NAJ]

Unfortunatly you are in a situation where you do not know what was done.
I can relate, we just had an 88 Mustang 5.0L traded in, they are sending it to auction but it idles at 1700 rpm and they wanted us to see if we could lower it.
We have 2 Mustang guys and they both said the car has replacement heads and larger injectors,it also has a Cobra upper/lower intake, larger throttle body and headers.
Well I found a couple of vacuum leaks which did not lower rpm.
We backed all the way off of the base idle screw which did nothing.
We checked ignition timing and it was way advanced, when we retarded the timing the idle came down but the car starting backfiring thru the exhaust on accel and a couple times thru the intake so we are assuming it was also cammed.
If you must you may want to put everything back to stock OE, get the car running right then start adding the mods one at a time.
This may also depend on weather the controller was upgraded.

[spooled up]

Quote:

Originally Posted by NAJ Also as someone mentioned the wastegate solenoid is not connected, what lines are running to the turbo?

Well I tried to get pics but no go. The only line I see is going from the boost controller to the wategate.

[NAJ]

While I was typing the post others posted including you and you mentioned a MBC so that explains why the wastegate solenoid is disconnected.

[janus]

let me also welcome you to the torquey TD world ;)

if there's a resistor on the MAP, i would also guess the ECU always see's higher engine load and therefore it's running super-rich? on the other hand, closed loop operation would try to trim some fuel out..

[91shelby]

how old is the O2 sensor? a failing O2 sensor could cause possibly that