stressed outttt

[89scottytona]

ok, here goes... car is running rich, as in 10 to 1 a/f. my vac gauge is reading 10" of vaccuum. obviously plugs are black. father in law put in 87 octance... all i ran is 93, and obviously there is an issue... i did a compression test, 125 across the borad. the car is running real rough, i pulled the wires off one by one, and noticed that 3 and 4 are not contributing as much as 1 and 2. had a code 52 and 12. i had a new map laying around, plugged it in, and it help a smidgent. does anyone have ideas??? oh yeah, car is a 89 Daytona Shelby, 2.5 t3/t4 hybrid, and a few other odd and ends. car is running on stock 89 2.5T1 cal, boost via mbc @ 12 psi. stock ignition timing too...

[bakes]

what is your fuel preasure at?

[89scottytona]

stock fpr, stock pressure and pump. pulled vac line off of vac block, sucked and blew on line to see if i can get gas out... nothing...

[forcedfedmopar]

i take it you actually looked at the plugs? Are you sure timing is on?

[BadAssPerformance]

i take it you actually looked at the plugs? Are you sure timing is on?

+1 check both ignition and cam timing

also, what t3/t4 hybrid? many many wheel/housing options

and what fuel injectors?

[glhs727]

Code 52 is a bad voltage reading (out od range) from the O2. When that code is set off the car goes full rich to make sure you don't blow it up. Get a new mopar oxygen sensor or NTK sensor. After you replace the sensor make sure you unplugged the battery to reset the computer.
The 10 inches of vacuum could be a vacuum leak or cam timing, although if it were low vacuum becuase of cam timing, I would think cam timing would be so far off it wouldn't run. If you have a bad vacuum leak causing low vacuum, the map will think the car is under load or moving and will dump a lot more fuel too, even though you are at idle.
later
Cindy

[89scottytona]

timing is dead on... stock everything, except the turbo and a fmic... the turbo is a 50trim. ignition timing has not been touched except for initial setup. (motor is 3 months old now), car was running awesome, then all of a sudden to this. the only hint i got something was going wrong was on the wideband it was showing 10-11 to 1 off throtlle cruising, then just tipping in to cruise it would fluxuate from a low 14 to mid 15. on decel it would go full rich, then to like 16-17 to 1 till i got back on it. then a few days later i noticed the check engine lamp would come on for a sec. then stay off. and run like poop... and yes i looked at the plugs... black as rich can be, oh and those are stock too, new of course. there are no audible vacuum leaks, i even unpluged the brake booster and capped of the nipple on the intake, no change.

[Abkshelby]

Listen to Cindy above.
Your 02 sensor has whacked out.
They get real unhappy when that sensor goes bad.
And don't put a piece of crap Bosch sensor in there.

[BLUEBALL]

Since its givin up a code that points to a fuel controlling sensor,go for that first. If its idling like crap,you prob gonna fix the low vac at same time when it smooths out.

[89scottytona]

will a O2 sensor crap out like that??? i never ever heard of something like that... funny you mention bosch... LOL it was what was available to get my car on the road... so, ma mopar or NGK???

[turbovanman²]

Simple test to rule out the ox sensor, simply disconnect it and reset the memory, if car runs great, get a new sensor, if not, you have other issues. If you have still have low vacuum, triple check your cam timing, it could have jumped. Check your fuel pressure.

[89scottytona]

i will do everything this weekend... it sux being a tow truck driver... lol so anyways, my gameplan is as follows... 1.) try out the O2 per turbovanman (not a fan of throwing parts...) 2.) spray intake and other vacuum related parts with carb and choke cleaner to see if i got leak.. any more suggestions???

[Abkshelby]

Or you can do it the right way and hook the car up to a scan tool and read the sensors. After you check the basics. Why people try to work on these things blind I have no clue. Best investment you will ever make is a scan tool.

[shadowdude]

Or you can do it the right way and hook the car up to a scan tool and read the sensors. After you check the basics. Why people try to work on these things blind I have no clue. Best investment you will ever make is a scan tool.

Not taking sides or kissing butt, but hell yes your right...i bought a OTC 3000 for my shadow and it was the best damn thing i ever spent money on for the shadow.If i may sneak a link in...

http://cgi.ebay.ca/OTC-4000-enhance-...item20b056fe75

[turbovanman²]

Or you can do it the right way and hook the car up to a scan tool and read the sensors. After you check the basics. Why people try to work on these things blind I have no clue. Best investment you will ever make is a scan tool.

Agreed to a point but a stuck ox sensors shows up on a scanner as, shock, a rich reading ox sensor, it WON'T tell you the sensor is dead, you need a multimeter, labscope for that. Easiest way it what I suggested.

[Abkshelby]

Agreed to a point but a stuck ox sensors shows up on a scanner as, shock, a rich reading ox sensor, it WON'T tell you the sensor is dead, you need a multimeter, labscope for that. Easiest way it what I suggested.

I've never needed to check a 02 sensor I suspected as bad with a multimeter. The readings on the scan tool assure me if the sensor is bad. If something is causing the sensor to hang rich that needs to be corrected first. Basics are presumed well before any sensors are even read. Plus the dude says he used a Bosch sensor. Turbo Dodge cars do not react well with them. They burn out prematurely. Others may say different but I know first hand they are junk.

[Abkshelby]

Not taking sides or kissing butt, but hell yes your right...i bought a OTC 3000 for my shadow and it was the best damn thing i ever spent money on for the shadow.If i may sneak a link in...

http://cgi.ebay.ca/OTC-4000-enhance-...item20b056fe75

And thank you for agreeing with me.
Few on here ever do and I usually just don't even offer advice anymore on here. A lot of these so called turbo Dodge experts I'd never let touch my cars.

[89scottytona]

thanx for the help thus far... i will be playing with the car tomorrow pending on the weather, hopefully its something wicked stooopid... it just dont make sense for this to happen...

[89scottytona]

ok... got to play a little... unplugged the O2, no change, no CEL, then again with the car in open loop (cold) i dont think the computer will even read it at that point... i then decided to unplug the coolant temp sensor and see if the car would run on base timing... HOLLY crap it runs better! the vacuum is around 18", which as i've noticed for the car is normal when cold. and its nice and smooth again! so... heres my thinking... bad hep, bad computer, or bad ECT sensor... thoughts???

[turbovanman²]

ok... got to play a little... unplugged the O2, no change, no CEL, then again with the car in open loop (cold) i dont think the computer will even read it at that point... i then decided to unplug the coolant temp sensor and see if the car would run on base timing... HOLLY crap it runs better! the vacuum is around 18", which as i've noticed for the car is normal when cold. and its nice and smooth again! so... heres my thinking... bad hep, bad computer, or bad ECT sensor... thoughts???

Well at this point, borrow a scanner or just put a coolant sensor is. Usually bad coolant sensors throw a code but if its running as bad as you say, then it could be the coolant sensor. You've ruled out the ox sensor as being bad, for now,

I've never needed to check a 02 sensor I suspected as bad with a multimeter. The readings on the scan tool assure me if the sensor is bad. If something is causing the sensor to hang rich that needs to be corrected first. Basics are presumed well before any sensors are even read. Plus the dude says he used a Bosch sensor. Turbo Dodge cars do not react well with them. They burn out prematurely. Others may say different but I know first hand they are junk.

Your a lucky man, I've diagnosed many a bad oxygen sensor using my labscope that showed up as good using a scanner. Scanners read at such a slow rate I've had sensors stuck at .4 and shown up as toggling on a sensor. Not trying to get in a pissing match here but a scanner is a tool, and can help diagnose issues, it does make it alot easier but it can be done without it, sometimes.