QuestionQUESTION: I just bought this car,used, for $300.00 with 99,000 miles. I can't get it to stay running. All the sensors I think have been replaced. One mechanic said it was running lean. It won't idle and just stalls out. It has a few mechanical issues also and is in overall fair shape. What could be wrong and do you think this car is worth fixing.
ANSWER: Hi Dave,
I have three suggestions:
1. Ask the engine computer for any stored fault codes in its memory. Use the ignition key to get the fault codes:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the check engine light, which remains "On", to begin to flash, pause, flash, etc. Count the number of flashes before each pause. Then repeat to be sure you have an accurate flash count set. Then group the counts in pairs in the order of appearance to form the flash fault codes. The last number will always be 55 which is the code for 'end of readout'. Then write back or go to www.allpar.com/fix/codes-html
2. Check the egr valve which may be stuck ajar slightly and that can cause a no idle/lean mixture situation. But tell me which engine you have so I can describe what to do to fix that.
3. Clean the throat, both sides of the valve plate, and the idle air passageway of the throttle body where air enters the intake manifold.
I believe you should be able to get it running better and I believe if there is nothing major wrong then you would do well to fix these minor issues.
Roland
PS Please 'rate' my answer, thanks.
---------- FOLLOW-UP ----------
QUESTION: Hi Roland,
Thanks for the quick response. It's a 2.5 non flex fuel. The codes I got were 12 and 22. Again,Thanks.
Dave
AnswerHi Dave,
The 12 code means the battery at some point in the recent past was disconnected, so that is not an issue. The 22 code means the engine coolant temp sensor is not reading properly (voltage too high or too low*), and that too would affect the mixture at start up and as the engine warmed up and ran when warm.
So get a new engine coolant temp sensor and install it. The sensor is screwed into the box on the front of the engine (the side which faces the front of the car) that also contains the thermostat, and is located between and slightly under spark plugs 3 and 4. Use some thread lubricant on the new unit so that it reduces the likelihood of binding up at a later time; use care in removing the old sensor to not damage the threads in the housing which are machined in the housing wall and would be difficult to repair if damaged. Rock the sensor gently back and forth to free it up for removal, after removing the wire connector (gently lift tab on side of connector). Before you begin that progect drain off about 2 quarts of coolant, coolect for reuse, by loosening the drain plug on the right lower corner of the back side of the radiator. That will lower the coolant level to be below that in the box so it won't come squirting out when you remove the old sensor. Then notice that there is a plug in the top of the box that is remove by means of an allen wrench (8 mm) and you should take that out too after the drain down, put some lubricant on its threads too. Then install the sensor, put on its wire connector. Then start to refill the coolant into the radiator's top cap opening and fill it until the coolant level rises into the sensor/thermostat box and reaches to the plug hole on the top. At that point put the plug back in. Then refill the system the rest of the way. This process is necessary so as to not trap air in the box and produce a erroneous temp reading.
The egr is dealt with as follows:
It is located behind the engine (between the engine and the firewall) and it is closer to the front of the engine so stand on the passenger side and look down and in behind the engine for the egr which has a pipe coming from the exhaust manifold to its underside and a pipe from it going to the intake. There is a vacuum operated round fitting on its top, and also a vacuum line going to an electrically operated valve closer to the engine, nearer the throttle body. Look under the round fitting (which is mounted on a saddle with openings for access to view) on the top of the valve where you will see a vertical rod with a slot in it which is the valve stem. Take a straight blade screwdriver and use the slot to lever the valve up against spring pressure and see if it is dropping back down due to spring's action and closing positively. Put WD-40 on the stem to loosen it up in that motion if necessary. Check to make sure the vacuum lines are all attached and not cracked. Then warm up the engine and observe the slot to see if it goes up when you rev the engine to 2500 rpm and then drops back down fully, closing the valve, when you let the engine go back to idle rpm. Make sure that the fully down position is really down because if it is not fully closing when you let go of the accelerator and coast that will cause the engine to stall. It may be that to get it to close you'll have to unbolt it and clean out the gas flow passage past the valve due to buildup of exhaust fumes in the valve as sticky crud deposit around the internal valve.
The other thing to verify is that the spark timing is set to 12BTDC with the coolant temp sensor's plug on the thermostat housing disconnected (the fan will come on when you pull that plug) and the engine warmed up.
Because of the throttle body fuel injection design you would need to work around and below the injector that hovers above the throttle plate. So I would only get involved with cleaning the throat/plate/air passageway if the above two fixed don't solve the problem.
Roland
PS Please let me know how it works out.
*One thought just came to mind: The coolant sensor may be unplugged or its wires may be damaged so look into that possibility first. Another possibility, though this would more likely produce a 17 code rather than a 22 would be that the reading is wrong because of air trapped in the box. That happens if someone drains and refills the system without pulling the plug on the box. You could try carefully removing the top plug just enough to allow the coolant in the system to begin to flow out of the hole which would remove all the air if that were trapped. Then start the engine and see if it runs better or not. But do this after you check out the egr valve. If the egr and bleeding out the air from the box don't work, then replace the sensor.
That is a long shot, but worth a try. You can erase the code 22 (but not the 12) by disconnecting the battery for 30 seconds or so. Then warm up the engine and recheck the codes. The 12 will still be there, and if the 22 doesn't reoccur then you won't need to change the sensor at all.
Sorry for all the detail, but I have this same engine and know its finer points.
