Saab Link Forums banner

2001 9-5 B235E Bio-Tuned - Stumbles/Stalls @ Start

2456 Views 7 Replies 3 Participants Last post by  BurnsSide42
So we have been running the 230hp Flex Fuel Bio Tune in our 9-5 from EPL performance for a few months. Recently I was made aware I am supposed to be running the T5 Turbo NKG's in it with said tune. Well - up until recently it was running on the OEM plugs (BCPR6ES) with no problems. It has recently been starting up "cold" and stalling out - restart and it stumbles and will rev up to clear up the funny burble. There is NO CEL as result of this - so I ordered a set of NGK's for a T5 Aero 9000 - BCPR7ES and it seemed like it was better - but was back to the same old game 2 days later. It seems to be more effected by the hotter outside air temp on the "cold start" as opposed to the cooler weather - not sure if this is just coincidence or what. My question to all you ECU project goers and anyone else - what plug should I use?
I have a set of the PFR7H10 on order to try - but I am just at a loss as to what could be causing this problem aside from spark plugs.
Gap is correct - no need to go there.
Anyone think a failing Throttle body could be the fault? Again - no CEL

I have to change the 25K old water pump as that is leaking already....

Engine was replaced @ 78K by previous owner under GOODWILL from Saab - 8K later they blew the head gasket when they ignored the leaking heater by pass valve.
Car now has 102,xxx miles on it since I replaced the HG @ 86K

I replaced the HG and have since re-torque the head (I believe it's warped still - but hard to say with a leaking water pump) Plugs I pulled out were just sooted (normal looking) aside the one which pulled a thread of cylinder 2 plug out with it... - new one threaded right in.... I have 2 spare T7 heads lying around I plan to get rebuilt - but after SOC I hope.

Car is going to SOC one way or another lol - it's our newest car and seems to be craving the most attention lately

Getting new front brakes soon
Needs BSR exhaust installed
Needs Koni Rear Shocks Installed
The list continues.......
See less See more
1 - 8 of 8 Posts
What do you run for fuel in it? Seen ethanol do some wierd stuff with a bit of moisture in it. Seems unlikely with the lack of CEL though (I'd expect a cat efficiency or misfire code)
well - 90% of the time we run Sunoco 89 OCT - today since it was down to 1/4 I poured a bottle of LUCAS fuel system cleaner in it and filled it with some SUNOCO 93 OCT. - I am going to see if this and those T5 plugs work out a little better. I was starting to think poor fuel quality myself - but this will be my test. I do need to change the fuel filter too - I have one, just haven't had the urge to lay on the rocks out back in the heat and get gas on my arm and hands.....
I replaced the HG and have since re-torque the head (I believe it's warped still - but hard to say with a leaking water pump) Plugs I pulled out were just sooted (normal looking) aside the one which pulled a thread of cylinder 2 plug out with it... - new one threaded right in.... I have 2 spare T7 heads lying around I plan to get rebuilt - but after SOC I hope.

The list continues.......
Hi Jeff, I have a T7 head new vavle job 5 k ago if you want it i will trade for a R head if one of yours is one, mine is not) or sell for 1/2 the cost of a valve job with parts...

ALos have a set of the PFR plugs if you want them new ( cheaper)
Hi Jeff, I have a T7 head new vavle job 5 k ago if you want it i will trade for a R head if one of yours is one, mine is not) or sell for 1/2 the cost of a valve job with parts...

ALos have a set of the PFR plugs if you want them new ( cheaper)
I believe both of mine are from E motors - not R's as they were both taken from Sludge cars or similar (heads were fine - just a little dirty in the VC area) One was a 9-5, other was a 9-3 (I believe both heads are the same)

Talk money/trade for head - what are we talking? I can get a cylinder head cleaned, checked - rebuilt for $150 plus parts. "Locally"
I believe both of mine are from E motors - not R's as they were both taken from Sludge cars or similar (heads were fine - just a little dirty in the VC area) One was a 9-5, other was a 9-3 (I believe both heads are the same)

Talk money/trade for head - what are we talking? I can get a cylinder head cleaned, checked - rebuilt for $150 plus parts. "Locally"
$100?? Its has new seals, a regrind, one new valve ( it was nicked)... oh and T5 cams ( but you can have the T7 ones for it.) If you want the cams another 50 say< i think they sell for 50... and I can meet you with it but I dont know where you are anymore???
Lansdale PA - I just moved a little south east from where I was in Telford. Nicer house and town - still shitty neighbors :) Next house will not have neighbors directly next to me.

$100 sounds fair - does that include the "core" trade as well? I don't need the T5 cams - as I can get them myself for less if I ever want to add them to the car.


Back to the topic - car started this morning with LESS of a stumble and did not stall - still not right, but better.
Back to the issue - I have NOT swapped plugs out yet. I have all 3 sorts on hand. Car still acts up on "initial" start of the day. Fires over - stumbles stalls instantly. Restart and it stumbles and runs with a burble/miss (like too much fuel) and clears up with a little throttle. Then it runs and drives fine all day. Restarts like nothing is wrong all day. Let it sit over night and the next day - same thing all over again.

Should I replace the FPR? I have one from a 2003 9-5 Aero laying around which was good. To me this is either a Fuel or Spark problem it seems...

Anyone? I replaced the Water pump, changed the oil and the trans fluid - all ready for SOC aside the starting issue.
1 - 8 of 8 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top