Crossfire idles high
Intermediate
Joined: Oct 2000
Posts: 48
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From: Katy, TX, USA
Once you get through with all the sensors, vacuum leaks, clean and rebuild the TBI's, (Check if you have excessive side to side play in your throttle shafts), (they may need to be bushed), balance the TB's, set timing etc., they will run quite well.
Thread Starter
Advanced
Joined: Jan 2009
Posts: 72
Likes: 4
From: Bulverde, Texas
Still no luck. So Far I have replaced the CTS, MAP Sensor, EGR, O2 Sensor. I sprayed carb cleaner and propane around the manifold and Throttle bodies, no diff. The 82 now just Idles low and rough, until it stalls. Then after about 20 min of operation it will start, but won't keep running. I still cant get any code other than 12. The only thing I havn't done is torgue the manifold down.
Any other Ideas?
Any other Ideas?
Le Mans Master
Joined: Apr 2001
Posts: 5,000
Likes: 1
From: Minneapolis, Mn USA
I wouldnt be surprised if the ECM itself isnt the culprit.
Does it still idle high or now just low and rough?
you can plug off the headlight system and the brake booster system to rule those out as well.
How does the injector spray cones look? Nice fine mist or streamy -as in low fuel pressure?
Just throwing out ideas.
Does it still idle high or now just low and rough?
you can plug off the headlight system and the brake booster system to rule those out as well.
How does the injector spray cones look? Nice fine mist or streamy -as in low fuel pressure?
Just throwing out ideas.
6th Gear
Joined: Mar 2008
Posts: 6
Likes: 0
From: lake jackson texas
Try removing and cleaning the idle air control valves. The car has 2 of these located near the fuel injectors. (ACDelco 217-406 Valve Assembly) If you have to replace them AC-Direct.com is the cheapest place.
Thread Starter
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Joined: Jan 2009
Posts: 72
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From: Bulverde, Texas
Rough Idle
Note: Would the headlights & brakes still work if there was a vacum leak?
Last edited by daleman; Feb 21, 2009 at 10:51 AM. Reason: add on
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Thanks, That could be it. After we changed the Fuel Pump & Filter, the car did run well enough for my son and I to drive a mile to the local pep boys. I recall checking the headlights to see if they worked when I got back. It ran like poo poo after that, so your idea may not be such a long shot after all. If that doesnt work, I may have to go after the ECM as Brent suggests. I can't spend too much on the car because it won't legally be mine until the probate hearing on March 18th.
Note: Would the headlights & brakes still work if there was a vacum leak?
Note: Would the headlights & brakes still work if there was a vacum leak?
The brakes will work but may take longer to get hard. They will seem spongly. Pull the plastic valve out of the brake booster. You should be able to blow through it only one way. Make sense?
It does not take much of a leak to mess things up. The TBI's operate on 6 inches of water not psi. Thats real sensitive. Image drawning a line on a straw and sucking water up to that line and having to hold it steady continueously...
Try the above see what happens.
You haven't messed around with any settings have you?
Jim
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Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Have you eliminated fuel starvation? You need to understand the system. the fuel pump sends fuel to the front TBI. There is a regulator in that TBI that maintains a constant fuel pressure somewhere between 9-13 psi. If the pump is only sending...say 6 psi...the regulator can not step up the psi to required 9-13 which will result in spuddering and stalling. The regulator only steps down the psi. I know you said you replaced the fuel pump. But did you examine the hose thats on the pump in the tank? Was it good? Are you sure you are getting 9-13 psi from the fuel pump? Did you go with an 82 pump or 85 pump? The volume on the 85 I think is around 36 psi.
Get in the car cold. Turn the key to on. Listen for the fuel pump...should go on for 2 second. Immediatley after you should hear a prime pulse from the injectors. Start the car (cold start). does the idle go up above 1200 rpm? Does it gradually come down to about 650-700 rpm as it warms? Is this when it start spuddering?
During spuddering is the gas coming out of the TBI's in a cone shaped pattern or is it spuddering out? A little dangerous but try pooring a little fuel into the TBI's when it spudders does it smooth out?
Jim
Get in the car cold. Turn the key to on. Listen for the fuel pump...should go on for 2 second. Immediatley after you should hear a prime pulse from the injectors. Start the car (cold start). does the idle go up above 1200 rpm? Does it gradually come down to about 650-700 rpm as it warms? Is this when it start spuddering?
During spuddering is the gas coming out of the TBI's in a cone shaped pattern or is it spuddering out? A little dangerous but try pooring a little fuel into the TBI's when it spudders does it smooth out?
Jim
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Hi Jim,
The Check enging light flashed without any pattern regardless of rpm. The car ran pretty good the first time I ran it after replacing the Fuel pump & Filter. I drove it about 3 miles total, to the gas station & back. I filled it with 91 octane. The next time I started it, it ran at 3000 rpm. For some reason, it doesnt do that anymore. It runs at low idle, but its rough. I can see both spray cones of fuel entering the throttlebody. The flow appears to be intermittent, but each TBI is acting the same as the other. If one TBI sputters fuel, so does the other. I can also smell unburned fuel. I changed the EGR last night, but still no change. Could the Coolant temp sensor be bad even though the coolant temp guage seems to be working. Or are they two separate reads.
The Check enging light flashed without any pattern regardless of rpm. The car ran pretty good the first time I ran it after replacing the Fuel pump & Filter. I drove it about 3 miles total, to the gas station & back. I filled it with 91 octane. The next time I started it, it ran at 3000 rpm. For some reason, it doesnt do that anymore. It runs at low idle, but its rough. I can see both spray cones of fuel entering the throttlebody. The flow appears to be intermittent, but each TBI is acting the same as the other. If one TBI sputters fuel, so does the other. I can also smell unburned fuel. I changed the EGR last night, but still no change. Could the Coolant temp sensor be bad even though the coolant temp guage seems to be working. Or are they two separate reads.
If you don't what to try the above. Go to Peep boys they must have an OBD 1 code reader.
Jim
Thread Starter
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Joined: Jan 2009
Posts: 72
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From: Bulverde, Texas
I have been using a code reader, but the code 12 IE blink pause blink blink, keeps on going. It doesnt stop after 6. I am a little woried about that fuel pump and filter deal. As I mentioned before. The car had been sitting for about 3 years with less than a half a Tank of gas when I got it. When I pulled the pump, I noticed the little black coupler hose was gone, and prabably still in the tank. I probably should have dropped the tank, and cleaned it out. Hind site 20/20. After replacing the pump & filter, It started right up, so it drove it to the gas station and back with no problem. It ran pretty good for sitting 3 years. Next day drove it with my son but tailight bulbs, and it started to progressively run more rough, and Idle high. Now it will only idle low until it cuts out. I havent messed with any settings other than replacing every scensor that I could find.
Racer
Joined: Oct 2006
Posts: 396
Likes: 3
From: Buffalo New York
You haven't mentioned replacing vacuum hoses. The vacuum hose from the manifold to the map sensor will affect fuel flow (rich) and idle speed (high) . It's worth it to replace all vacuum hoses. Also check the IAC valve to see if it's sticking. Finally, check the coolant temp sensor wiring.
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
I have been using a code reader, but the code 12 IE blink pause blink blink, keeps on going. It doesnt stop after 6. I am a little woried about that fuel pump and filter deal. As I mentioned before. The car had been sitting for about 3 years with less than a half a Tank of gas when I got it. When I pulled the pump, I noticed the little black coupler hose was gone, and prabably still in the tank. I probably should have dropped the tank, and cleaned it out. Hind site 20/20. After replacing the pump & filter, It started right up, so it drove it to the gas station and back with no problem. It ran pretty good for sitting 3 years. Next day drove it with my son but tailight bulbs, and it started to progressively run more rough, and Idle high. Now it will only idle low until it cuts out. I havent messed with any settings other than replacing every scensor that I could find.
Thats a good sign. If it ran right after you replaced the pump and filter then thats where we should be looking.
I assume you replaced the pump and filter sock in the tank. Did you also replace the filter under the car?
Its possible some debi got by and has blocked something. There is an orfice in the rear TBI. Could it be fouled up? You can take it apart and clean it. Just don't dis assemble the area that the regulator spring is in. Only remove the top half of the TBI. You may want to get a gasket set first.
Jim
Thread Starter
Advanced
Joined: Jan 2009
Posts: 72
Likes: 4
From: Bulverde, Texas
The TBI & Manifold bolts were a little loose. Torqued em down 24 ftlbs ea. Still no good. Only this time when I steped on the gas while trying to get it to start, fire shot up through the TBI about 10". Not like'n it. I wonder how much a new ECM would cost.
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
