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Re: Two things Posted by Cmyles [Email]  (#1126) [Profile/Gallery]
(more from Cmyles) on Tue, 21 Jun 2011 08:11:35
In Reply to: Re: Two things, Todd N, Mon, 20 Jun 2011 15:29:44 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Toddn,
One of the likely probabilities is that one or more injectors is stuck wide open. It would be some coincidence for all four to be so stuck unless it is the result of something in the fuel or something that someone did (misguided maintenance). Are all four spark plugs sooted up? When you did the spray patter test did they appear to be pulsing at all (rapidly) or just spraying constantly? The ECU opens the injectors (all at the same time) 12 times per second but the duration of each of those openings can be short or long depending on sensor input so with no load you should be able to see some pulsing of the spray. If the injectors are not stuck open then something is telling the ECU that there is a lot of air moving through the induction system and that points to the AMM. Alternatively, when the throttle is wide open the throttle position sensor tells the ECU to enrichen the mixture so maybe you have a TPS problem like shorted wires or a defective micro-switch inside the TPS. Unplug the TPS and connect a VOM between pins 2 and 3 (middle pin and pin closest to the front of the car) and you should only have continuity when the throttle is opened beyond 72 degrees (nearly wide open). If you have continuity on those two pins with the throttle closed then the TPS is defective. Shorted wires at that connection would give the same bad signal to the ECU and make it go to full load enrichment. You may have a defective ECU that is getting the correct signals from the various sensors but decides that there is a ton of air blowing through the induction system and tells the injectors to go to wide pulse (tons of gas) but I'd suspect a bad sensor (like the AMM or TPS) or a bad connection first and check those things. A good LH diagnostic book will be really helpful for you.
posted by 198.233....
, Sun, 19 Jun 2011 21:20:10
, Sun, 19 Jun 2011 23:48:24, Mon, 20 Jun 2011 10:20:16, Mon, 20 Jun 2011 11:33:02, Tue, 21 Jun 2011 08:11:35 <-- Viewing This Message
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