QuestionHi Roland, I´m Brian(i´m the one with a Cirrus 96 LXi 2.5L Car) again, sorry bother you.....Yesterday i replace the engine coolant temperature sensor with a new one and my car still have the same problem, after about 7-10 min, begin to fail until shut down, it seems is drowned.... I checked the fault codes and there is no one. The symptoms are:
1. When my car begin to fail, the tachometer moves slowly with littles jumps down and up, like my car was drown, and keeping going until my car dies. The jumps of the tachometer become bigger when the car fails more.
2. The "CHECK ENGINE" ligth, start to flash, and is flashing until my car dies.
What other sensor could be the problem?. Or it´s posibble the PCM it´s wrong?, What else could i check?.
Like i say to you before, i replace Cranshaft sensor, and the Distributor..
Hope you can keeping help me...
AnswerHi Brian,
PPS I doubt the timing belt is bad because the engine runs well for a while. You can remove the covers at the front of the engine where the camshaft sprockets are located (one at the top of each bank of cylinders and look at it, cranking the engine just a bit then look again, etc. If the timing marks on sprokets line up simultaneously with the respective slit marks on the cover back halves (you will have to crank the engine by hand using a socket on the crankshaft pulley to move the engine gradually to the mark positiion) then that would be a pretty good showing. To verify further than that would require more dimantlement so I wouldn't recommend that.
The OBD tester interpretation is beyond my understanding without the instruction manual as to how to interpret its readout. But one way to look at it is that it has noticed an 0134 code. If that is not true then ignore what follows. That code says that the oxygen sensor is stuck in the middle voltage range, i.e., is not responding to how the actual mixture might be setting at. I would suggest that you take a look at the wiring to the oxygen sensor mounted on the rear exhaust manifold to be sure those wires are ok and the tip to which they are attached isn't damaged. Even if those pass, I would consider replacing that sensor. The fact that the engine works for a few minutes and then goes bad is consistent the changeover from preset operating conditions to conditions where are the sensors are callen into play (so-called closed loop operation). So before that time occurs, the engine will operate based on its design and preset parameters, but then it is supposed to operate better with less pollution after it warms up. At that point it relies on accurate sensors. But if the oxygen sensor is indeed stuck (not working) then the engine will not adjust to the needs. Then you might well have an imperfect mixture of fuel to air. So I think that may be what is going on, but I can't guarantee it. You could try a free readout at Autozone just in case.
That is my best advice. I hope it works out.
Roland
PS Another thing to do is to get a fault code readout using the underdash access plug and a OBD-II fault code reader. There are many possibly relevant codes that are not available via the check engine light. You can get a free readout at an Autozone parts store if there is one near you, or an independent shop will do a readout for about $40. Ask what are the fault code 4-digit numbers, what they mean, what to do, and how much? Then write back and tell me the results and we can compare notes. I suspect there is something going on that is not going to be revealed by the check engine light.
Roland
Hi Brian,
The only other temp sensitive sensor is called the intake air temp sensor and it, along with the MAP sensor are located at the front end of the intake manifold. It is directly adjacent to the power steering fluid reservoir. It has two wires: black/light blue and black/red. Remove the plug by gently lifting the tab. Then measure the resistance across its terminals. Exactly like the coolant temp sensor it should read 7,000 to 13,000 ohms when cold, and when the engine is fully warmed up it should read 700-1000 ohms. So check that out. If that is ok then it appears that there is something going on with the pcm, but check out this sensor first.
Roland
