OK mechanics, why do I STILL have a rough idle on my 84 crossfire???
05-05-2010, 07:23 PM
#1
Racer
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OK mechanics, why do I STILL have a rough idle on my 84 crossfire???
UPDATE:
SCAN TOOL RESULTS CAN BE FOUND HERE:
http://www.box.net/shared/dezqgixy4p
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> >
1984 Crossfire with only 50,000 miles – EXTREMELY well cared for by original/PO.
And I baby this thing also.
Developed a surging 600 to 400 to 600 to 400 to 600 rpm type rough idle a few months after I bought it.
Other than that, she runs PERFECTO.
Never stalls or hesitates or lacks power – no misses - no knocks - I can smoke ‘em easily – and it cruises like new - I just can’t resolve this damn rough idle thing
So here is what has been done to date (and yes I have a FSM):
• No codes or vacuum leaks detected by a Chevy dealer or myself
• No slack or play in the TB shafts – it is like new – told by mechanic they are balanced
• Rebuilt original injectors by Jon at FIC
• New Bosch Platinum Iradium plugs (non-gappable, four electrodes)
• New MSD cap, rotor and coil
• New Magnecor KV25 wires
• Replaced both IAC’s - TWICE!!!
• New air cleaner temp sensor
• New K&N air filter
• New TBI gaskets
• K&N air cleaner sealer
• New TPS
• New MAP
• New ESC
• New oxygen sensor
• New EGR valve
• New EGR solenoid
• New fuel filter - pressure seems fine
• Cleaned vacuum lines
• New PCV
• Disconnect/reconnect the battery
• Never stalls or hesitates – just that damn rough idle
This is getting really frustrating fast.
Any tips on what else I should try???
Here's what I'm thinking about next:
* rebuild fuel cover/fuel regulators (diaphrams)
* maybe do a vacuum / TB balance myself
* temp sensor for the ECM
* air injection system components
* replace the ECM itself
* replace all that cannister crap up by the front drivers headlight
* get an OBD 1 reader - even though I already know how to do the Check Engine blinking count - memory thing
* give up (never - won't happen)
Thanks.
Dave H. dchoran@athenet.net
SCAN TOOL RESULTS CAN BE FOUND HERE:
http://www.box.net/shared/dezqgixy4p
OK gang - I got a CP9185 and recorded the info.
Just click on the above link and you can view all of it.
Can somebody tell me if this looks normal???
Or what are the things in red below?????
Anything in there that would effect/resolve my rough idle?????
FYI - frames 15 thru 20 are when I gave it gas to 3000 rpm. It recorded like 36 frames.
And the idle went to 1000 rpm as soon as I plugged the tester in. Back to ~600 when the tester was unplugged.
REALLY NEED SOME EXPERT ADVICE HERE - HELP!!!!!!!!
Thanks.
Dave H.
dchoran@athenet.net
Here is a sample frame - I know what some of these are - others I have no clue???
Vehicle Data List
CODES PRESENT NO --- already new that
AC REQUEST OFF --- air cond
BLM 126 --- no clue ???
CLEAR FLOOD OFF --- wot???
COOLANT(øF) 195 --- yeah, my dash reads the exact same
CRANK SWITCH OFF --- starting the engine???
ENGINE RPM 1000 --- logical
EXHAUST 02 RICH --- constantly fluctuated rich lean rich lean, normal???
IAC POSITION 38 --- idle air controller positions, moves up as I hit the gas
INTEGRATOR 130 --- no freaking clue???
LOOP STATUS CLSD --- again, no freaking clue???
MAP(V) 1.16 --- mass air pressure, new unit
O2S(mV) 524 --- oxygen sensor, new, bounced allot
O2S CROSSCNTS 149 --- oxygen huh, no clue???
P/N SWITCH R/DL --- no freaking clue
PROM ID 3911 --- ECM serial number???
TCC LOCKUP NO --- no clue, EGR???
TCC SOLENOID OFF --- no clue, EGR???
TPS SENSOR(V) 0.61 --- I set this myself with a voltmeter when installing a new one - right on
VEHSPEED(MPH) 0 --- glad I wasn't moving since I was "texting" on the 9185
Frame: 1 Time: 1.1 --- reference point
Just click on the above link and you can view all of it.
Can somebody tell me if this looks normal???
Or what are the things in red below?????
Anything in there that would effect/resolve my rough idle?????
FYI - frames 15 thru 20 are when I gave it gas to 3000 rpm. It recorded like 36 frames.
And the idle went to 1000 rpm as soon as I plugged the tester in. Back to ~600 when the tester was unplugged.
REALLY NEED SOME EXPERT ADVICE HERE - HELP!!!!!!!!
Thanks.
Dave H.
dchoran@athenet.net
Here is a sample frame - I know what some of these are - others I have no clue???
Vehicle Data List
CODES PRESENT NO --- already new that
AC REQUEST OFF --- air cond
BLM 126 --- no clue ???
CLEAR FLOOD OFF --- wot???
COOLANT(øF) 195 --- yeah, my dash reads the exact same
CRANK SWITCH OFF --- starting the engine???
ENGINE RPM 1000 --- logical
EXHAUST 02 RICH --- constantly fluctuated rich lean rich lean, normal???
IAC POSITION 38 --- idle air controller positions, moves up as I hit the gas
INTEGRATOR 130 --- no freaking clue???
LOOP STATUS CLSD --- again, no freaking clue???
MAP(V) 1.16 --- mass air pressure, new unit
O2S(mV) 524 --- oxygen sensor, new, bounced allot
O2S CROSSCNTS 149 --- oxygen huh, no clue???
P/N SWITCH R/DL --- no freaking clue
PROM ID 3911 --- ECM serial number???
TCC LOCKUP NO --- no clue, EGR???
TCC SOLENOID OFF --- no clue, EGR???
TPS SENSOR(V) 0.61 --- I set this myself with a voltmeter when installing a new one - right on
VEHSPEED(MPH) 0 --- glad I wasn't moving since I was "texting" on the 9185
Frame: 1 Time: 1.1 --- reference point
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> >
1984 Crossfire with only 50,000 miles – EXTREMELY well cared for by original/PO.
And I baby this thing also.
Developed a surging 600 to 400 to 600 to 400 to 600 rpm type rough idle a few months after I bought it.
Other than that, she runs PERFECTO.
Never stalls or hesitates or lacks power – no misses - no knocks - I can smoke ‘em easily – and it cruises like new - I just can’t resolve this damn rough idle thing
So here is what has been done to date (and yes I have a FSM):
• No codes or vacuum leaks detected by a Chevy dealer or myself
• No slack or play in the TB shafts – it is like new – told by mechanic they are balanced
• Rebuilt original injectors by Jon at FIC
• New Bosch Platinum Iradium plugs (non-gappable, four electrodes)
• New MSD cap, rotor and coil
• New Magnecor KV25 wires
• Replaced both IAC’s - TWICE!!!
• New air cleaner temp sensor
• New K&N air filter
• New TBI gaskets
• K&N air cleaner sealer
• New TPS
• New MAP
• New ESC
• New oxygen sensor
• New EGR valve
• New EGR solenoid
• New fuel filter - pressure seems fine
• Cleaned vacuum lines
• New PCV
• Disconnect/reconnect the battery
• Never stalls or hesitates – just that damn rough idle
This is getting really frustrating fast.
Any tips on what else I should try???
Here's what I'm thinking about next:
* rebuild fuel cover/fuel regulators (diaphrams)
* maybe do a vacuum / TB balance myself
* temp sensor for the ECM
* air injection system components
* replace the ECM itself
* replace all that cannister crap up by the front drivers headlight
* get an OBD 1 reader - even though I already know how to do the Check Engine blinking count - memory thing
* give up (never - won't happen)
Thanks.
Dave H. dchoran@athenet.net
Last edited by dchoran; 05-15-2010 at 04:03 AM.
05-05-2010, 08:25 PM
#3
Racer
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Location: Appleton, Wisconsin Boston originally - North End
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see answers in blue
What is the base idle set at? - after warm up ~600 (in gear)
Is it stable? no- 600 -500-400-500-600.......
What is manifold vacuum at idle? - maybe I should buy a gauge and check myself
Is it stable? - don't know
Do you have access to a scanner? nope - but the blinking check engine light sequence shows no active or stored codes - just 12 - one blink pause two blinks - FSM says that is normal
What is the base idle set at? - after warm up ~600 (in gear)
Is it stable? no- 600 -500-400-500-600.......
What is manifold vacuum at idle? - maybe I should buy a gauge and check myself
Is it stable? - don't know
Do you have access to a scanner? nope - but the blinking check engine light sequence shows no active or stored codes - just 12 - one blink pause two blinks - FSM says that is normal
Last edited by dchoran; 05-05-2010 at 09:41 PM.
05-05-2010, 08:42 PM
#4
Melting Slicks
Yeah, you may want to do a balance and vac check yourself. How does your mechanic know its balanced. Did he actually balance them? If so which method did he use?
What did you gap your plugs at?
Typical idle problems are usually vac related.
Have you tested the operation of the IAC?
Whats your fuel pressure?
is that idle in Park or while in Gear?
What did you gap your plugs at?
Typical idle problems are usually vac related.
Have you tested the operation of the IAC?
Whats your fuel pressure?
is that idle in Park or while in Gear?
05-05-2010, 09:29 PM
#5
Racer
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qws
Yeah, you may want to do a balance and vac check yourself.
How does your mechanic know its balanced. - they are the experts aren't they - I trust him
Did he actually balance them? - bad assumption maybe on my part?
If so which method did he use? - no clue, maybe I'll ask
What did you gap your plugs at? - see original post
Typical idle problems are usually vac related. - thanks for the tip!!!
Have you tested the operation of the IAC? - replaced with new ones twice.
Whats your fuel pressure? - high don't have a gauge - yet
is that idle in Park or while in Gear? - idle warm in gear 600
How does your mechanic know its balanced. - they are the experts aren't they - I trust him
Did he actually balance them? - bad assumption maybe on my part?
If so which method did he use? - no clue, maybe I'll ask
What did you gap your plugs at? - see original post
Typical idle problems are usually vac related. - thanks for the tip!!!
Have you tested the operation of the IAC? - replaced with new ones twice.
Whats your fuel pressure? - high
don't have a gauge - yetis that idle in Park or while in Gear? - idle warm in gear 600
Last edited by dchoran; 05-05-2010 at 09:42 PM.
05-05-2010, 09:49 PM
#6
Melting Slicks
qws
Yeah, you may want to do a balance and vac check yourself.
How does your mechanic know its balanced. - they are the experts Aren't they always
Did he actually balance them? - bad assumption maybe- maybe No disrespect to anyone but sometimes the mechanics don't know how either, took my mechanic 3 times the first time he changed my cam a few years ago... and he didn't know you had to add a zinc additive!
If so which method did he use? - no clue
Two common methods are used. Mamometer or you can adjust by using a feeler gauge
What did you gap your plugs at? - see original post - Gotcha
Typical idle problems are usually vac related. - thanks for the tip!!! No sarcasism there!...lol
Have you tested the operation of the IAC? - replaced with new ones twice.
Great you replaced them but do they work?
Whats your fuel pressure? - high don't have a gauge - yet - would make a good investment for you, as would a Helms FSM manual
is that idle in Park or while in Gear? - idle warm in gear 600 mmmmm when mine was CFI it would idle at 600 in gear and warm as well
:
Yeah, you may want to do a balance and vac check yourself.
How does your mechanic know its balanced. - they are the experts Aren't they always
Did he actually balance them? - bad assumption maybe- maybe No disrespect to anyone but sometimes the mechanics don't know how either, took my mechanic 3 times the first time he changed my cam a few years ago... and he didn't know you had to add a zinc additive!
If so which method did he use? - no clue
Two common methods are used. Mamometer or you can adjust by using a feeler gauge
What did you gap your plugs at? - see original post - Gotcha
Typical idle problems are usually vac related. - thanks for the tip!!! No sarcasism there!...lol
Have you tested the operation of the IAC? - replaced with new ones twice.
Great you replaced them but do they work?
Whats your fuel pressure? - high don't have a gauge - yet - would make a good investment for you, as would a Helms FSM manual
is that idle in Park or while in Gear? - idle warm in gear 600 mmmmm when mine was CFI it would idle at 600 in gear and warm as well
:
05-05-2010, 10:32 PM
#7
Safety Car
I had problems on one vehicle with aftermarket spark plugs. It was throwing codes and was running not like usual - I switched back to stock plugs and the problem was over. It's probably something simple that you're missing.
05-05-2010, 11:07 PM
#8
Instructor
My car does almost the same thing: idles fine, but once you put it in gear, it slows WAAAY down and threatens to die. I've been fooling around with adjusting the idle, and it's slowly coming around.
05-05-2010, 11:11 PM
#9
Team Owner
Member Since: Oct 2004
Location: altered state
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St. Jude Donor '05
Had a similar problem on a TBU truck and it was a number of different items combuned. ECM injectors bad cat 02 sensor. Not telling you to throw parts at it just what worked for me. The EGR passage in the intake was plugged solid also.
Once fixed was the smoothest idling vehicle Ive ever owned (even moreso than the ZR1 which has a rep for being smooth)
Once fixed was the smoothest idling vehicle Ive ever owned (even moreso than the ZR1 which has a rep for being smooth)
05-06-2010, 11:05 AM
#11
Former Vendor
If you can get a scanner, you can see the actual sensor readings. They may not be far enough off to set a code, but still cause a problem. A lot of times you'll see something that is flucuating up and down with the idle. What is the base timing set at? Is it stable?
05-06-2010, 01:11 PM
#12
Instructor
That's pretty much the same problem I'm having with my idle only I don't have a scanner adaptor for an ODBI, all I have is the OBDII computer. I've been looking for one though. I just have a key for mine and it really don't tell you much.
05-06-2010, 01:31 PM
#13
Le Mans Master
Check your wire looms for what shape they are in. Mine was running badly due to the wires dropping down onto the exhaust manifold. One actually burned.
The arching caused a miss and poor idle.....Once it was opened up it ran fine...but at low RPMS is was nasty.
The arching caused a miss and poor idle.....Once it was opened up it ran fine...but at low RPMS is was nasty.
05-06-2010, 06:29 PM
#14
Team Owner
Pro Mechanic
I agree w/the person who said to look for vacuum leaks. Especially the intake lid gasket, but look everywhere.
I also agree w/the person that recommended that you check your fuel pressure.
Lastly, though you mechanic may call himself an "expert", I seriously doubt that he is a Crossfire expert. Not that there is anything magical about the CFI, but there are a few unique procedures and idiosycracies...and balancing TB's and lid leaks are two of them. Low fuel pressure is a third.
I also agree w/the person that recommended that you check your fuel pressure.
Lastly, though you mechanic may call himself an "expert", I seriously doubt that he is a Crossfire expert. Not that there is anything magical about the CFI, but there are a few unique procedures and idiosycracies...and balancing TB's and lid leaks are two of them. Low fuel pressure is a third.
05-06-2010, 06:46 PM
#15
Racer
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Location: Appleton, Wisconsin Boston originally - North End
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Again - nice tips from the CF experts out there
I had this exact problem BEFORE the new plugs/wires - so I don't think that is a factor. Timing has not changed.
My TB linkage is TIGHT AS A (deleted) - no slop - no play. This car was babied and well cared for all 26 years and 50,000 miles. NEVER beat on by the PO - just the opposite.
My wires are NEW $125 Magnecors.
I got new looms too and made sure everything was carefully wired, spaced, zip tied, etc..... There are no engine misses or spitting out the tailpipes. Just an unstable idle.
My EGR was fairly clean and passage way looked fine - lightly sooted.
Is there an OBD sensor out there that reads an '84 in action??? Every place I go they just jump the A+B terminals and watch the check engine light flash - dang, I can do that. The FSM gives you the low down on codes - I just don't have any but #12.
I am beginning to think maybe there is a vacuum leak I cannot find or hear.
What is the SAFEST way to check for vacuum leaks??? I really don't want to be spraying starting fluid all over the place
Does somebody make "thick heavy smoke in a can"????
THANKS again everybody
Dave H.
I had this exact problem BEFORE the new plugs/wires - so I don't think that is a factor. Timing has not changed.
My TB linkage is TIGHT AS A (deleted) - no slop - no play. This car was babied and well cared for all 26 years and 50,000 miles. NEVER beat on by the PO - just the opposite.
My wires are NEW $125 Magnecors.
I got new looms too and made sure everything was carefully wired, spaced, zip tied, etc..... There are no engine misses or spitting out the tailpipes. Just an unstable idle.
My EGR was fairly clean and passage way looked fine - lightly sooted.
Is there an OBD sensor out there that reads an '84 in action??? Every place I go they just jump the A+B terminals and watch the check engine light flash - dang, I can do that. The FSM gives you the low down on codes - I just don't have any but #12.
I am beginning to think maybe there is a vacuum leak I cannot find or hear.
What is the SAFEST way to check for vacuum leaks??? I really don't want to be spraying starting fluid all over the place
Does somebody make "thick heavy smoke in a can"????
THANKS again everybody
Dave H.
Last edited by dchoran; 05-06-2010 at 06:53 PM.
05-06-2010, 07:58 PM
#17
Instructor
The computer I have sells attachments for different cars that you plug into the end and then it fits different models and makes. They cost about $15 each, but I never really needed any of them. They sell the attachments for Honda and Ford, GM OBDI and OBDII. I wish I wouldn't have thrown my packaging away. Here's the website, though. www.CanOBD2.com
Hope that helps.
Hope that helps.
05-06-2010, 08:02 PM
#18
Instructor
05-06-2010, 11:46 PM
#19
Le Mans Master
Use a propane welders torch for vacuum leaks.
Just get the cheapo Blue can with a tip from the Hardware store. open it up and run it around the engine bay....if it ignites, you'll see it....it's not like it will explode or anything. it'll just make that poofffffff sound they make when you put a match to it....
Just get the cheapo Blue can with a tip from the Hardware store. open it up and run it around the engine bay....if it ignites, you'll see it....it's not like it will explode or anything. it'll just make that poofffffff sound they make when you put a match to it....
05-07-2010, 04:20 AM
#20
Racer
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Use a propane welders torch for vacuum leaks.
Just get the cheapo Blue can with a tip from the Hardware store. open it up and run it around the engine bay....if it ignites, you'll see it....it's not like it will explode or anything. it'll just make that poofffffff sound they make when you put a match to it....
Just get the cheapo Blue can with a tip from the Hardware store. open it up and run it around the engine bay....if it ignites, you'll see it....it's not like it will explode or anything. it'll just make that poofffffff sound they make when you put a match to it....
That is just what I don't want to do - sounds risky - don't want to lose any facial hair or burn down the house - or worse yet, burn up my '84.
I'll save the poofffffing for my gas grill
Dave
Last edited by dchoran; 05-07-2010 at 10:47 AM.