Omg please some one tell me
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
Omg please some one tell me
What is wrong with this freaking car!
85 bone stock performance chip 160 thermo new TPS IAC Valve, Fuel Pump plugs, wires
I raced it last week in a auto x and it seemed down on power, i got on the express way and when i hammer the throddle to tghe floor it seems like it bogs down like its starving for fuel (but you can smell it burning rich) No smoke. I get home the knock sensor wire was off. it threw a code 43 (knock sensor) The cap that hold it on the sensor is broken.
I put a clamp on it lightly to hold it on.
I too it to my mechanic to have the TPI dialed in. he adjusted the TPS and Idle. No codes ran fine
I drove it tonight and it started again I hammer on it and it just doesnt want to go. if i feather the trottle it will accelerate. It is not throwing any codes.
WHAT IS IT? I swear i am about to get a for sale sighn. THIS IS WHY I AM CONSIDERING A CARB SET UP!
PLEASE HELP!!!!!!
85 bone stock performance chip 160 thermo new TPS IAC Valve, Fuel Pump plugs, wires
I raced it last week in a auto x and it seemed down on power, i got on the express way and when i hammer the throddle to tghe floor it seems like it bogs down like its starving for fuel (but you can smell it burning rich) No smoke. I get home the knock sensor wire was off. it threw a code 43 (knock sensor) The cap that hold it on the sensor is broken.
I put a clamp on it lightly to hold it on.
I too it to my mechanic to have the TPI dialed in. he adjusted the TPS and Idle. No codes ran fine
I drove it tonight and it started again I hammer on it and it just doesnt want to go. if i feather the trottle it will accelerate. It is not throwing any codes.
WHAT IS IT? I swear i am about to get a for sale sighn. THIS IS WHY I AM CONSIDERING A CARB SET UP!
PLEASE HELP!!!!!!
Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
Start with fuel pressure reads - static, idle with vacuum on FPR, idle with vacuum off of FPR, and pedal down - gauge taped to windshield.
Then do Mr jon's injector check per his video.
I think that will tell you much.
Then do Mr jon's injector check per his video.
I think that will tell you much.
Melting Slicks
Joined: Aug 2003
Posts: 3,407
Likes: 400
From: Lakeville MI
Sounds like you have developed a rich condition which likely carbon-fouled the plugs.
I'd check the plugs first to confirm the richness and troubleshoot the fuel system for sources of an overly rich mixture. If they're all black, then you're generally rich, if its only 1 or two that are fouled, then check the specfic wires.
Leaking injectors, leaking regulator, excess fuel pressure, overly large injectors, maf sensor, maf sensor calibration in the tune, coolant temp sensor, or excess frictional load can all contribute to an overly rich mixture.
A couple of fouled mis-firing plugs can increase the load (airflow per rpm) which can further increase the mixture enrichment while in open loop contributing to even more fouling and rough running.
Fouled cylinders on the driver's side can also adversely affect closed loop by creating a false lean condition, contributing to even more richness as the ecm compensates.
I'd check the plugs first to confirm the richness and troubleshoot the fuel system for sources of an overly rich mixture. If they're all black, then you're generally rich, if its only 1 or two that are fouled, then check the specfic wires.
Leaking injectors, leaking regulator, excess fuel pressure, overly large injectors, maf sensor, maf sensor calibration in the tune, coolant temp sensor, or excess frictional load can all contribute to an overly rich mixture.
A couple of fouled mis-firing plugs can increase the load (airflow per rpm) which can further increase the mixture enrichment while in open loop contributing to even more fouling and rough running.
Fouled cylinders on the driver's side can also adversely affect closed loop by creating a false lean condition, contributing to even more richness as the ecm compensates.
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
With the above, but is the car doing this when cold, warm, or both? An injecter ohm test probably won't reveal much, the '85s had bosch injectors which are not prone to failure like the multecs.
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
Its driving me nuts can you bypass the knock sensor.
I swear taht carb set up is sounding better and better
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
the fuel system needs to be thoroughly diagnosed. Yes it sucks but part of having a 24 yr old fuel injected car. Its a strong possibility that your fuel pressure regulator is on its way out. Check to see if any fuel is coming out of the vacuum port.cwyates4, yes the multechs are prone to failure but that doesnt mean the Bosches wont fail either, after all they're over 20 years old. New injectors will outperform those old ones even if the originals arent completely bad yet. All of mine were still within spec when I replaced them but I noticed an increase in power, responsiveness, and fuel economy. I went from 21 mpg to nearly 25 mpg on the highway
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
the fuel system needs to be thoroughly diagnosed. Yes it sucks but part of having a 24 yr old fuel injected car. Its a strong possibility that your fuel pressure regulator is on its way out. Check to see if any fuel is coming out of the vacuum port.cwyates4, yes the multechs are prone to failure but that doesnt mean the Bosches wont fail either, after all they're over 20 years old. New injectors will outperform those old ones even if the originals arent completely bad yet. All of mine were still within spec when I replaced them but I noticed an increase in power, responsiveness, and fuel economy. I went from 21 mpg to nearly 25 mpg on the highway
I am at a loss. I truley love this car, but it is driving me nuts.
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Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
Not recently but i did when i put the fuel pump in. It is not long enough for me to see while driving. The pump held good pressure and good back pressure after the new fuel pump.
Ill check again tonight
Burning Brakes
Joined: Apr 2004
Posts: 762
Likes: 2
From: Huntington ma
Here's a guess (if you wanted to start throwing parts at it..) - ignition coil.
Won't set a code - OBD1 system has no way of looking at the secondary side of the ignition system. Coil winding insulation resistance can/will break down as temps come up and the resulting misfiring just gets worse and worse.
Happened to me on My '85 - would run great when Cold, as Soon as it started to get up near normal coolant temp it would begin to fall on it's face under load/acceleration. A new ignition coil (Finally - I won't go thru the list of everything I tried and replaced) fixed it.
Won't set a code - OBD1 system has no way of looking at the secondary side of the ignition system. Coil winding insulation resistance can/will break down as temps come up and the resulting misfiring just gets worse and worse.
Happened to me on My '85 - would run great when Cold, as Soon as it started to get up near normal coolant temp it would begin to fall on it's face under load/acceleration. A new ignition coil (Finally - I won't go thru the list of everything I tried and replaced) fixed it.
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
Here's a guess (if you wanted to start throwing parts at it..) - ignition coil.
Won't set a code - OBD1 system has no way of looking at the secondary side of the ignition system. Coil winding insulation resistance can/will break down as temps come up and the resulting misfiring just gets worse and worse.
Happened to me on My '85 - would run great when Cold, as Soon as it started to get up near normal coolant temp it would begin to fall on it's face under load/acceleration. A new ignition coil (Finally - I won't go thru the list of everything I tried and replaced) fixed it.
Won't set a code - OBD1 system has no way of looking at the secondary side of the ignition system. Coil winding insulation resistance can/will break down as temps come up and the resulting misfiring just gets worse and worse.
Happened to me on My '85 - would run great when Cold, as Soon as it started to get up near normal coolant temp it would begin to fall on it's face under load/acceleration. A new ignition coil (Finally - I won't go thru the list of everything I tried and replaced) fixed it.
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
Ok i got new plugs, Dist Cap, and Coil. I will start there. all togather it was 60 bucks.
HOWEVER how do i put a new knock sensor wire? just soder it? or does any one know where it goes into.
HOWEVER how do i put a new knock sensor wire? just soder it? or does any one know where it goes into.
Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
I know that coil is Very old. and the cap looks kinda ratty. The plugs are cheap. so why not. and of course im rich I have a corvette! isnt that what every one thinks!
Racer
Joined: Dec 2007
Posts: 450
Likes: 9
From: SOUTH NJ
Burning Brakes
Joined: Apr 2004
Posts: 762
Likes: 2
From: Huntington ma
You can get a new connector and lead wire for the knock sensor (the squeeze type "nipple" connector) at most any auto parts store. Just cut off what's left of your Old connector and solder (or crimp together, if you choose) the new one to the wire. Fixed.
You Really don't want to "bypass" that knock sensor, or leave it disconnected...
You Really don't want to "bypass" that knock sensor, or leave it disconnected...
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
Ok I plan on doing the knoc sensoe wire next,
I changed the dist and the rotor button was loose on one sie, i when ahead and changed plugs. Guess what STILL SCREWED UP! you atek off normal no problem, but you mash the gas and it cuts in and out and stumbles. let off the gas its fine. it does it above teps of 190. My buddy thinks its the catalitic converter? Any Ideas I am realy at a loss here! If i cutt it off will it screw up the ECM readings? My mechanic says it has some polution controll on it?
IF it does not get diagnosed or fixed soon its getting a for sale sign! I am mgetting very tired of this, I was a ford man for many years and this is my first bow tie. I am not impressed as of yet with the dependability of this car.
I changed the dist and the rotor button was loose on one sie, i when ahead and changed plugs. Guess what STILL SCREWED UP! you atek off normal no problem, but you mash the gas and it cuts in and out and stumbles. let off the gas its fine. it does it above teps of 190. My buddy thinks its the catalitic converter? Any Ideas I am realy at a loss here! If i cutt it off will it screw up the ECM readings? My mechanic says it has some polution controll on it?
IF it does not get diagnosed or fixed soon its getting a for sale sign! I am mgetting very tired of this, I was a ford man for many years and this is my first bow tie. I am not impressed as of yet with the dependability of this car.
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
O2 sensor, plain and simple. 
could still be the ignition control module or clogged cat, but I'd bet the house on the o2.
When the car gets warm, look at the catalytic converter, if its clogged, it'll be glowin'.
could still be the ignition control module or clogged cat, but I'd bet the house on the o2.
When the car gets warm, look at the catalytic converter, if its clogged, it'll be glowin'.
Last edited by cwyates4; Aug 10, 2008 at 02:02 PM.
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
Sounds like a clogged cat and PLEASE learn to spell and you can put a comma or period in there every once in a while.Kidding aside, sounds like a clogged cat and don't solder the connection, get a new connector.