My van has 320,000 miles on it and has been running beautifully until last year. The van has problems starting and staying running in cold and wet weather. I've had the cold start valve replaced, new plugs, egr valve, timing chain and oxygen sensor replaced. Still no difference, in fact it's now getting worse. Now it's hard starting every morning. Once it warms up it runs fine. What could this possibly be???
and has been running beautifully until
On Sat, 12 Jun 2004 09:22:10 -0700, lilround guy rearranged some electrons to form:
Plug wires, distributor cap, rotor
It sounds like you may have a sensor out of range. Have you had the vehicle ECM scanned by a competnet tech with a good scanner such as the Ford STAR scanner. Even if there are no stored codes, a factiry spec scanner can perform more detailed testing and better results. A handheld scanner at Autozone may not do the job. That said and even if you have checked for codes, have you tried resetting the ECM. This can be done by disconnecting the battery for about 20 minutes. Restart the engine without touching a thing and let it idle for 10 - 15 minutes to allow the ECM to start it learning process. Before actually driving, move the trans selector into and out of each position several times as well as operating the air conditioning to help it relearn it's idle parameters. Drive the vehicle around town a few miles to allow the ECM to relearn the vehicle driving parameters. You should then be able to re-scan the ECM for fault codes. Many times they will show up after this process where there is a marginally performing sensor. Sometimes, this will correct the condition if the ECM has for some reason been corrupted. That said, I have found the ECT sensor either out of spec or a bad connection on several vehicles where cold start/operation are a problem. BTW, the O2 sensor will almost never effect cold start as it is not in the loop until after about the first 90 seconds after the engine starts. The ECT, TPS and a couple of others are in the loop during starting. Lastly, I don't know what you are calling a cold start valve unless you are talking about the ISC which operates all the time when the engine is doing something. The ECM uses it to maintain proper idle speed anytime the engine is starting or running.
Hey thanks alot about the responce but ya kinda went over my head on this one. You kinda lost me on the ECT, TPS & ISC. I'm more of a amatuer back yard mechanic and I don't know what those are lol. I did notice that the van was running rich though if that helps any.
Oh by the way I did have it scanned at my mechanic and nothing was coding.
ECT = engine coolant temperature; this is what computer uses to determine whether engine is cold or warm or somewhere in between. It is not the same sensor as the one that operates the guage on the dash - only the computer "sees" it. Located front left side of intake manifold - easy to change. Have seen several with bad connections.
TPS = throttle position sensor. Computer uses it to determine homuch "gas" you are giving it. Throttle should only be depressed when driving. There is a case where the engine may become flooded and you would full depress the throttle to clear the flooding. The computer will sense full throttle while cranking and turn off the fuel injectors to clear the flood.
ISC = idle speed control which does just that any time the engine is running. Your engine has no cold start valve.
Since you say the engine is running rich, I would also check the fuel pressure. If the regulator fails, the fuel pressure will go skyhigh resulting in a very rich condition. Sometimes, the regulator diaphram fails resulting in fuel being dumped directly into the intake. This will not set a fault code in many cases if the computer is able to compensate on it's own. You have to test for it with a fuel pressure testor. If you pull the vacuum line and find fuel, the regulator is definitely dead.
If you do not have some basic knowledge of the system and how it works, you can spend a fortune throwing parts at if with the only results be a greatly reduced bank account and a bad attitude. There is a great publication on Ford Fuel Injection by Probst which explains how the system works and how to troubleshoo it. Many public libraries have it. You can usually find a copy online for about $25US. If you are screwing around with Ford EFI, it is well worth it. There are several sites on the net which explain Ford abbreviations and ECM fault codes and how to extract them from the EEC-IV system.
Check the coolant temp sender.. Sends the coolant temp to the computer (not the one for the gauge). I've done 2 in the last 12 months, it can go bad and tell the computer it's -30 degrees when it's not. Steve
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