2001 v70 t5 acceleration surge, check engine blinking

Post by **corradoandt5v70** » 03 May 2011, 18:03

my 2001 t5 just started a strange hesitation that comes in waves when I accelerate hard and the check engine light flashes but does not stay on. I have changed the plugs, turbo control valve and fuel filter (all oem) with no results. Anyone else had this problem?

FCPEURO · Post by **FCPEURO** » 04 May 2011, 16:27

Have you checked for Vacuum leaks? Also, check to see if any codes are stored in the computer. It could be a bad sensor on it's way out.

Post by **JRL** » 04 May 2011, 17:28

A flashing light is either a miss or a VERY serious issue
Since it goes out, i would guess you have a miss

Post by **corradoandt5v70** » 04 May 2011, 17:51

I took it in to my mechanic today and he told me the CEL flash was most likly a misfire and I might want to bring it in to test the coils. I wanted him test them today but he only had time to pull the codes (none) so I went out and picked up 5 new coils as mine are 10 years old now anyway. I will know tommorow if that was my issue.. it is raining very hard here now in new hampshire, if that does not solve the problem its on to a more comprehensive vacuum check. Thanks and I will post the results soon.

Post by **corradoandt5v70** » 04 May 2011, 19:37

Change of plan, I'll need a few more days because I have to return the oem coils I Picked up for $88.00 a piece.I linked onto IPD through this amazing site and found the HD coils for half the price and I can wait a bit for that kind of money, Thank you MVS

Post by **corradoandt5v70** » 07 May 2011, 14:28

New coils in and she runs perfect, no more CEL and hesitation is gone!!. Upon close inspection 2 of my old coils had hairline cracks and that was the problem. Its nice to have it running 100% again ,thanks MVS.

wwilme · Post by **wwilme** » 17 Jul 2012, 20:45

My '01 V70 T5 with 172k on it has had a similar problem of late. About 30k miles ago I drag raced my wife in our then new to her Mini Cooper (a replacement for her '01 v70XC). In doing so I wound the motor out fairly close to the redline and not a minute later got the tell tale rough idle and a heavy miss accompanied by the CEL. (by the way, a T5 Volvo will waste a non S Mini) I got home and quickly narrowed it down to the no 3 cylinder coil pack. One aftermarket coil pack later all was well. Fast forward two years and I found myself having to avoid a car flying way to fast as it crested a hill on the way to work. I floored the T5 and again probably brought the car near to redline for a moment or two. That night on the way home from work in heavy traffic and near 100 degree temps, the exact same miss appeared. It would do it for a while and then disappear. The next day it was intermittent, but again near 100 degree temps. I had bought an extra coil pack on eBay the last time this happened so I'd be ready. That weekend by pulling the plugs to the coil packs starting with cylinder no 1, I found the issue to be the cylinder no 4 coil pack - of course it had to be under the turbo hose. I replaced it with my spare, but that made no difference. I then played musical coil packs to make sure my "spare" was not a dud and that the original no 4 was indeed bad. I now appear to have 6 good coil packs. But pulling the plug on no 4 continues to make no difference in the performance when the miss is present. And it isn't always. I'ver gone over the wires that feed the plug as far as I can see without pulling off a bunch of flexible wire cover to investigate further. (as a side note, much of it seams to be disintegrating in my engine compartment) Its been two weeks and I can't get the car to repeat the symptoms full time, so it's hard to diagnose. The car always runs fine when started cold. The symptoms show up after 20 or 30 miles of running and it seems to be exasperated by outside temperature - we have been experiencing a serious heat wave on the east coast. Last week I experienced my first flashing CEL, but reading up in the MVS, it seems that is more because the car was under heavy load than anything else. I did have 5 people in it with the A/C going in 100 degree weather. What to do next, short of taking it to the dealer? Any help appreciated!