| Author |
Message |
Anthony Tipton (Tonyt)
New member
Username: Tonyt
Post Number: 15
Registered: 5-2001
| | Posted on Sunday, July 07, 2002 - 12:36 pm: | |
Well my saga continues through the July 4th holidays. Have confirmed that the fuel system is working just fine. Have also confirmed from the dealer that the spark plug wires are fine for my car, although I still have not eliminated them as a possible cause.
My original exhaust system had an EGR valve in one of the intermediate pipes. However the previous owner had disconnected the vacuum line to it so I figured no exhaust gas was flowing into the intake. When I replaced the exhaust system this winter I also replaced the intermediate pipes without an EGR valve and simply blocked off the pipe into the intake manifold.
Now my question is, is it possible that the EGR valve was functioning slightly and allowing some exhaust gas into the intake and now, with none entering from the exhaust, the engine is running rich?
Any thoughts. I'm grasping at straws but running out of potential causes.
Thanks,
Tony |
Chris A. (Asianbond)
New member
Username: Asianbond
Post Number: 35
Registered: 5-2002
| | Posted on Saturday, July 06, 2002 - 1:03 am: | |
Hi Anthony, sorry that my suggestion that it may had been a fuel problem did not panned out for you. I took the easier route in just driving the car to burn off any water or bad fuel. I don't have answers to your questions. Best of luck in finding the problem.
Cheers,
Chris |
Anthony Tipton (Tonyt)
New member
Username: Tonyt
Post Number: 14
Registered: 5-2001
| | Posted on Friday, July 05, 2002 - 7:38 pm: | |
Well in going through my check off list of potential causes I decided to check for water in the fuel. Broke the fuel tank to fuel pump line at the fuel pump. Only about 6 cups of gas came out of the gas tank. I though this very strange because the tank is between one-half and three-quarters full. But no more would dribble out. This was beginning to defy some basic laws of physics. The only semi-logical explanation was that there was one hell of a vacuum in the fuel tank. So I re-connected the fuel line and broke the vapor line between tank and charcoal canister. Upon opening the fuel line gas began pouring out.
Now thinking that I had found the problem I blocked off the vacuum line to the charcoal canister and started the car up. Ran just as badly as before.
Still baffled by this fuel tank thing. Not sure that it is somehow not related to the bad running problems.
Anyone got any thoughts on why the fuel stopped coming out and whether it is perhaps a sign of an underlying problem I'm missing. Oh, there was no water in the gas.
Tony |
Larry Fletcher (Fletch62)
New member
Username: Fletch62
Post Number: 3
Registered: 6-2002
| | Posted on Friday, July 05, 2002 - 10:52 am: | |
Check the plunger in the fuel distributor to see if it is sticking. If it is that would cause your type of problem. Contact me if so, my business is rebuilding fuel distributors.
Larry Fletcher
CIS Flow Tech LLC |
Anthony Tipton (Tonyt)
New member
Username: Tonyt
Post Number: 13
Registered: 5-2001
| | Posted on Thursday, July 04, 2002 - 9:12 am: | |
I have reviewed a number of threads on this forum dealing with spark plug wires. Seems to be alot of differing opinions on important features.
My first thought was that the plug wires were my problem but only because they were different than what I took off the car. Had a difficult time understanding exactly why the non-resistor wires would cause the problem I'm encountering.
The ignition box certainly can't sense the wire resistance. Is it possible that the electromagnetic interference from the wires is picked up by the ignition box?
Trying to solve the problem by "method of elimination". Therefore I will probably change the wires back to original just to remove them from the equation of potential causes. Performed check on cold start relay, it is not the problem.
Would take the car somewhere to be looked at but doesn't run well enough to even allow it to be backed out of the garage.
Tony |
Charles I Claussen (Atlantaman)
New member
Username: Atlantaman
Post Number: 13
Registered: 3-2002
| | Posted on Wednesday, July 03, 2002 - 10:22 pm: | |
it is my understanding that if you do not use factory wires-then Magnacor is the only suitable alternative--the digiplex is extreemely picky about the resistance of the lines |
Anthony Tipton (Tonyt)
New member
Username: Tonyt
Post Number: 12
Registered: 5-2001
| | Posted on Wednesday, July 03, 2002 - 3:29 pm: | |
No their are no oxygen sensors. Coil wires have good connectivity. I will check the cold strat relay tonight. Not sure how to check the WUR. But the comments on the spark plug wires has my interest. I replaced the extenders with stock replacement parts but the plug wire I got from England. It is for a 308 but is non-resistor type wire, ie copper wire. The wires I took off the car were resistor wires. Didn't think this would matter much to anything but the radio, which I removed.
Did I make a mistake using non-resistor type plug wires?
Tony |
Chris A. (Asianbond)
New member
Username: Asianbond
Post Number: 29
Registered: 5-2002
| | Posted on Wednesday, July 03, 2002 - 10:01 am: | |
It maybe a more simple problem than you think, it could be water in your gas, after a car sits for a while water forms in the gas tank. STRONGLY suggest that you drive the car for a bit to see what happens, sometimes it burns off and everything runs back to normal. It happen to me in my 911 several times. Typical clues were it idles roughly and does not have want to go when you gas it. |
Charles I Claussen (Atlantaman)
New member
Username: Atlantaman
Post Number: 12
Registered: 3-2002
| | Posted on Wednesday, July 03, 2002 - 8:28 am: | |
my 2 cents worth:
1--I hope you replaced teh plug wires with ferrari parts--the digiplex is VERY sensitive to the amount of resistance in the wires.
2--ANY missing or unhooked vaccuum lines can do this to you too-check to be sure there are no open vacuum nipples |
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas
Post Number: 383
Registered: 3-2001
| | Posted on Wednesday, July 03, 2002 - 6:04 am: | |
The 83' doesn't have an 02 sensor. From the problems described I would guess the WUR also. A pressure test will be able to give you an accurate diagnosis. |
Kurt Kjelgaard (Kurtk328)
Junior Member
Username: Kurtk328
Post Number: 120
Registered: 3-2001
| | Posted on Wednesday, July 03, 2002 - 2:06 am: | |
A thermocouple is a temperature sensor.
It is fitted to the cat and monitors cat temperature.
Turns on the slow down light if too hot. |
Donny Bridges (Wildcatfans)
Junior Member
Username: Wildcatfans
Post Number: 61
Registered: 9-2001
| | Posted on Tuesday, July 02, 2002 - 11:13 pm: | |
You didn't drive it at all after the work?
I'm not sure but I don't think 83's had an o2 sensor, it just runs open loop. Anyhow it doesn't matter because the lambda loop doesn't close until the engine warms up. Mark's check is quick, but that solenoid is only a one time shot of fuel to get it started up, so I doubt it would cause the surging you described. My guess is the warm up regulator. It varies fuel pressure during startup to increase rpms. You can check the voltage at the connector, there should be 12 volts all the time, also check the resistance across the connector on the WUR. I can't remember the value you should see but it definitely should not read no resistance. You may have to take some fuel pressure readings to troubleshoot the problem. I bought a Bosch K-Jetronic test kit that has a gauge and all the connectors. It really helps when looking for problems like this.
Email me if you would like to discuss further. |
Mark Collins (Markcollins)
New member
Username: Markcollins
Post Number: 2
Registered: 7-2002
| | Posted on Tuesday, July 02, 2002 - 4:40 pm: | |
Check the cold start relay, or an easier way to prove if this is the problem is to disconnect the blue connector on the righthandside of the airbox. restart the engine if it runs fine either the blue connector needs cleaning or the relay needs reseating/ replacing |
Anthony Tipton (Tonyt)
New member
Username: Tonyt
Post Number: 11
Registered: 5-2001
| | Posted on Tuesday, July 02, 2002 - 4:10 pm: | |
Hate to sound stupid, but what is a thermo coupler? Is this some emission related equipment? |
Keith Rudd (Rpmcars)
New member
Username: Rpmcars
Post Number: 2
Registered: 7-2002
| | Posted on Tuesday, July 02, 2002 - 3:20 pm: | |
Just to ask but have you checked the o2 sensors, because you just replaced the exh. sys were they left undone? |
Greg Owens (Owens84qv)
Member
Username: Owens84qv
Post Number: 457
Registered: 10-2001
| | Posted on Tuesday, July 02, 2002 - 12:10 pm: | |
I know this may sound stupid, but make sure the coil wires (all of them) are snug tight to the coil. I thought mine were but they weren't.
I went through a period of time where my 308 was running similar to how you described. I went wire by wire and made certain that everything was secure. I recrimped every connector and closed the gap on every spade. Once reconnected, it's ran like a champ.
At least once a week while I'm checking oil and coolant levels, I also check the connectivity of the coil wires. Haven't had any problems for 6 months now. |
Anthony Tipton (Tonyt)
New member
Username: Tonyt
Post Number: 10
Registered: 5-2001
| | Posted on Tuesday, July 02, 2002 - 11:44 am: | |
Just completed some minor work to my 83 308qv which included rebuilding water pump, new Tubi exhaust system, new plug/coil wires and the like. Has been sitting idle since April and the engine ran like a charm prior to shut down.Finally got around to starting her up the other day and what a terrible sounding engine. Would only run for a couple of minutes during which it was surging between 1500-2500 RPM's and the smell from the exhaust smelled like raw fuel.
Pulled a couple of plugs from each bank and yep they were black as coal and smelled like fuel. Although the engine was surging on the tachometer I couldn't really tell any difference by sound. Probably because the engine was running so poorly to begin with, in fact it sound more like it was gurgling that running. When I pulled the vacuum line going to the digiplex from the intake it made no difference in engine operation which seemed odd.
I'm now at the point of needing to go through systems one at a time in a logical sequence to identify the problem. Will have to do this myself since the nearest mechanic to work on Ferrari's is 300 miles away.
Could anyone give me some pointers with where to begin looking and various testing to isolate the problem. It's obviously something fairly major and I assume related to something I did but I'm out of ideas.
Tony |