Ok so just a quick note about me, I am a professional auto tech with 15 yrs experience and ase certs honda toyota blah blah blah. More importantly this nutty volvo. I bought it from a friend and no joke an hour later it is broken bad. Here are some symptoms and what ive tried. Rough idle, hesitation, something i will describe as a jutter on attempted accel. Now some facts ETS light is on and has been for a while. Car goes in and out of limp mode (i assume this) car sometimes has niod to #1 #2 #4, sometimes not, has no pcm signal to #2 coil. I am begging for some ideas. Am I looking at a bad ETM causing all this, Is the PCM shot, is it potentially bad pcm ground or socket connections. I am at a loss. By the way alternator voltage is 13.96v, I have cleaned all ground connections I could see easily, I took the ETM off and cleaded and stared at it (staring seemed to do no good, odd). HELP!!!

 

What year and model Volvo needed first!

 

Oh yeah, that will help eh. I really am not an idiot just frustrated and tired I have been on this all day. Anyway 1999 VOLVO V70 XC 5cyl turbo AWD. Thanks.

 

No worries.... I would say check your MAF. Seems to be a weak point on all Volvos. Unplug it and see how it runs.

 

Yeah I been there too, the first time i unplugged it while running it died. Then I unplugged it and started it tryin to throttle it to keep running and could but the other issues still seemed to be there. I have never seen a bad maf cause lack of noid or no coil signal, can that do that on volvo cars?

 

The other thing to check is your throttle positioning sensor. Also another weak point.

 

On my 850, when the MAF started going it gave me an "Odd" idle and also the car would cut out. I unplugged it and it ran a little better. I got a new one and all the "hickups" went away.

 

I understood the tps to be contained inside the TCM is there another one somewhere else? If so could you tell me where?

 

Are the MAF units expensive for theese cars?

 

niod? Possible coil problem.

 

Any codes stored?
How many miles?

The TPS is in the electronic throttle body. The ETM might be bad. Bad part is that it most likely just went out of the extended warranty on it. If that is bad you will end up spending about $1200.00 to fix it.

Also make sure one of the intercooler hoses did not blow off.

 

NOID is acronym basically meaning "computer" signal to the injector. I am a master technician and an trained to replaced nothing until scientifically sure of the problem so my thinking goes like this. Cyl #2 is misfireing so why? check to see if spark is present, no it was not so why? spark plug is new, coil works on other cylinders so coil is ok, so i go further, what fires the coil we need power, ground, and pcm signal to "fire" the coil i checked all this and the signal is missing meaning it is not being sent or not reaching the coil, I checked the continuity of the signal wire form as near to the pcm as i could get and the wire has no shorts or excessive resistance. So I am down to either the pcm is bad or connection to the pcm is loose of this ETM is bad and causing wierd issues as I am somewhat unfamiliar with volvo control systems and this unit all togather.

 

Also did you test the cam position sensor?

 

TECH, I checked the hoses, this is a wierd one. It has 150k on it. The wierd thing to me is why do the problems change? I had no noid then I had it, the #2 coil signal is dead. Is the component known as the powertrain control module in most vehicles bad?(I dont know the volvo proper term) anyway what info can I give you to help figure this out? My scanner will only access the engine management codes which are misfire codes, well thats kinda obvious. And injector circuit codes where i had them unplugged using the niod light. I guess bottom line can the ETM cause ALL this or am I barkin up the wrong $1200 tree.

 

TECH, no I have not checked the CPS, I saw no codes to that effect. I have the vantage pro so I will do a component level test in the am as well.

 

Also, tech thanks for lookin at this for me.

 

Well I do not think the ETM would cause cyl #2 to drop. Do you have no signal to only the injector or to both the injector and coil?

Does your scanner read real time Data?

 

How do you get the control modules out of this car? I just started down this path as it got dark and I hung it up for the night. I thought I would look at the connectors for corrosion as I have seen that cause irratic behavior in other cases.

 

It is a pain I always take the box off first. The you will see purple sliders you will need to use a small long screwdriver to slide each side a little at a time till it works loose. There is a special tool you are supposed to use to get them out.

 

Well thats whats so wierd. This car ran fine. the ets loight was and had been on for months. I pay for the car and on the way home it develops a hesitation so I tear into it. Injectors are right there so I yank #1 it made no difference, all others did. S I pull the cover off and check plugs all new. So I check coil the coil seemed dead so I swapped it with no.2 now 2 was dead. Shut it off and started lookin at maf, looked fine. went back to check noid and was missing on 2 cyls, then checked coil signal and now it is gone on #2 (WTF). So I go back over it and as it stands now all coils are ok, cyl #2 has no coil signal, cyl #4 has no noid. And when you mash the throttle it revs very slowly and tops out at 3k rpm(limp mode?)