hello im having serious issues with my car.I have a 1998 v70 t5 with 142k miles. couldnt come at a worse time. if i miss work monday im fired... anyway my car has rough idle and as the rpm's raise as i go down the road it improves. while driving though i get a flashing check engine light. i have replaced my plugs and plug wires. when i code tested at advance i get a cylinder 4 misfire and a vaccum issue. i will try to get the exact code tommorow for it. i have had the vaccum code since a little after i got the car. never had a real issue except when i had to replace the plugs when it was doing a similar rough driving around 9-10 months ago. i replaced the plugs and when i was pulling them out the electrodes or whatever on the end of cylinder 2 plug was white and corroded. any ideas on what my current issue is would be GREATLY appreciated. i was thinking of trying to replace my fuel filter or replacing my injectors. dont know much about turbo cars but im a quick learner.
thanks
-kelley

 

I responded in the other thread before I saw this one. You give a lot more info here. You should first, as I said in the other thread, check your fuel pressure. You should also inspect ALL vacuum lines. They will cause a rough idle if you've got a bad vacuum leak. A fuel filter is cheap, injectors are not, so check your pressure before you do anything. You could blow a ton of cash on injectors and they could be just fine. If you fix any bad vacuum lines, have good fuel pressure, inspect and replace if needed any plugs and wires, and you STILL have rough idle it may be your injectors.

 

should i take a thing of carb cleaner and spray the lines? thats the best way i know to check them. yeah sorry i figured it would be better to actually make my own thread. as to fuel pressure i dont have a way to check. any ideas would help

 

If you have a vacuum leak bad enough to cause rough idle it'll be visible, whether it's a disconnected or broken/rotted hose. Check with your local O'Reilly's or Advanced Auto Parts, they may rent one. Assuming you have the 2.3L Turbo, there is a fitting on the right side (looking at the engine from the front of the car) of the fuel rail. There is a blue cap on it and the fuel pressure gauge attaches there. I can check VADIS to see what pressure you should be getting.

 

The fuel pressure should be: 210-31 0 kPa for aspirating engines 210-380 kPa for Turbo engines

 

yeah i have the 2.3l turbo. i know exactly where you are talking about. when i was regapping the plugs to .28 i figd that was were i would put a tester. guess i have a busy day. i hope to have this fixed tomorrow. thanks for all the info so far

 

I hope you mean gap them to .028, not .28.....

 

yeah i always forget to type the zero. my lil brother went to get the plugs and had them put in at advance and they gapped them to .046......

 

I believe spec is .027, Tech can correct me if I am wrong however I am fairly sure I read .027 in VADIS and thats what I gapped mine at.

 

no dont get me wrong. im sure you are right. what that guy gapped them too seemed waaaaaaaaaay too high. i was saying he was just an idiot who didnt take the time to read a gap tool.

 

You should check the gap. At that spread you'll chance not getting spark under high boost. Any luck on checking the fuel pressure?

 

got all the plugs regapped. my brother was supposed to take the car to his friends shop to check the fuel pressure but of course they didnt do anything. so today im gonna do everything i can to get one.

 

well i called around and none of the local places rent out fuel pressure gages or do loner tools... im sure that is partly because of the shady aspect of people who live in the area. i code tested and got the same p0304 cyl 4 misfire and a new p0102 maf or vaf low circuit voltage. what is the VAF? and where is the MAF located on car? is it coming out from the air box?

 

MAF is just off the airbox. Take a look at the plug wire for #4, inspect both ends for corrosion and tight connection.

 

im going to try switching to an old plug wire and im ordering a new MAF today. there goes my paycheck lol. i totally disconnected the MAF and the car ran just the same as it has been. so that pretty much sold me on getting a new one. i tried spraying the inside with brake cleaner to clean the sensor and it made no difference. just bad i guess

 

The misfire is probably the only reason it is running rough. Did you ever disconnect the MAF with the key on? I believe this will give you a low signal code.

 

yeah ive changed plugs plugwire distributor cap and rotor button and MAF. it feels like im not getting compression and power till the turbo spools. i tried pulling out today and pedal to the floor it was like there was no power till 2500 rpms.