Mazda Rotary Club

General => General Technical => Anything Engine/Performance/Tuning related => Topic started by: yogibear on April 01, 2008, 08:25:45 PM

Title: Over boosting As of this morning
Post by: yogibear on April 01, 2008, 08:25:45 PM
Hi All

Took the car out this morning and once it had warmed up I put my foot down. When the second turbo kicked in the boost went up to 1.2 bar and then I think the pfc cut the fuel. This is now happening everytime I put my foot down the boost shoots up. Ive got an Apexi AVC-R boost controller which is set to 0.6 bar off boost and the PFC is set to 0.6 Bar of boost as well. I havent changed anything at all setting wise or anything else. The turbos were rebuilt about 1000 miles ago. Gonna pull it into the garage tonite to have a bit of a poke around.
The idel goes up and down a bit which I havent been able to trace either when you first start it it idle is fine and after it has run for a bit it drops to 850-900 rpm. Then after you have driven for a bit and stop the idle will go up and down between 700-1000 rpm seeking I think it is called.
Any suggestions would be appreciated.
Title: Over boosting As of this morning
Post by: rx7veilside on April 01, 2008, 09:06:19 PM
check the pipes to the wastegate sounds like u are losing boost control..i had a pipe left off by someone and i overboosted to 1.5bar:2eek :2eek
Title: Over boosting As of this morning
Post by: yehreally on April 01, 2008, 10:32:02 PM
yogibear. Do a search under \'hunting\' - thats the irratic idle. Had the same problem with twins and after much advice turned out to be a cracked turbo manifold. Car mileage was around 90K.
 
rx7veilside. Also have an AVCR on a single turbo and boost recently went to 1.5bar followed by a \'pop\' and the car wouldn\'t start :eek: turned out to be a cracked tip even thought was set at 1 bar max....still unsure of why this happened and car being checked for pipe leaks which might cause overboost.....
Title: Over boosting As of this morning
Post by: yogibear on April 01, 2008, 11:23:05 PM
Rite well that was an interesting experiance. Took all of the induction pipes off and checked all of the pipes to do with the boost control. Couldent find any problems chaecked all of he connections no problems. Put it all back together checking everything very carefully no probs.

Took it out on the road and it boosted up to 1.00 bar before pfc cut it out. Changed the boost settings on the pfc to 1.3 to see if that made any difference. Oh boy it did was wheels spinning up the road in third gear with the AVC-R showing boost went up to 1.35bar. Think it would have kept boosting if i hadent have lifted if.

So im wondering if the AVC-R has packed in as it doesent seam to be controling the boost at all at present. Gonna go n have a bit of a reasearch on the subject.

1.35 bar of boost is good fun lol :)
Title: Over boosting As of this morning
Post by: leon on April 02, 2008, 09:56:41 AM
Also go bang engine fun if your not setup right :driving  Is there any gain settings on the ACV-R? it might have lost its memory and gone back to factory settings?
Title: Over boosting As of this morning
Post by: Red and Single on April 02, 2008, 11:50:12 AM
^^^ yep

I\'m waiting for the my engine has gone bang thread :rollin
Title: Over boosting As of this morning
Post by: yogibear on April 02, 2008, 02:02:11 PM
Nah it aint gonna happen, being very carful not to put my foot down. Thinking its probably either the solanoid or the wastegate thats the problem. Gonna try n check the solanoid when I get home tonite. Ive got spare wastegate in my garage as well not sure if ive got time to swap that over tonite as well though.

My run of bad luck continues though. My front end was moved over 1/2" when a landrover ran into me a month ago and on the way into town this moring to get the tracking looked at the locking bonnet pin twisted out and the bonnet came up and is snapped doen the middle of the underside. Told the insurance company it wasent rite but they have said they wont give me a courtosy car.

U know when u think things cant get any worse
Title: Over boosting As of this morning
Post by: ro284 on April 02, 2008, 04:03:45 PM
Bad luck mate! Could that bump with the landrover also be causing your engine problems?
Title: Over boosting As of this morning
Post by: yogibear on April 02, 2008, 07:34:24 PM
I dont know it just seams to have moved the wings over and the bumper. Cos they are fiberglass they have all cracked.

Its prob gonna go to reworx to get fixed so ill ask them to look at that as well if I havent sorted it all ready
Title: Over boosting As of this morning
Post by: yogibear on April 02, 2008, 11:27:43 PM
Help please guys. Im getting nowhere. I checked the boost controler solanoid 2 nite and its working. I also checked the actuaters and they are working. I also checked that the boost controller was working and it is working.

What should I check next as this is really starting to do my head in :(
Title: Over boosting As of this morning
Post by: leon on April 03, 2008, 09:40:33 AM
Have you checked the pipes that go to the actuators? not just visual give them a bend see if you can see any cracks/splits as they may look perfectly fine before you touch them :Giggle (story of my life) also the otherboost does it happen at a certain time?
Title: Over boosting As of this morning
Post by: skybusr34 on April 03, 2008, 10:35:31 AM
sounds like split actuator hose to me
Title: Over boosting As of this morning
Post by: yogibear on April 03, 2008, 11:00:13 AM
Rite im gonna go through all of the hoses tonite and replace all of them and hopefully that will halp.

Its happening with both tyrbos not just the secondary.

Dont think its The Apexi AVC-R boost controller but hay its a rotary so it could be anything lol.
Title: Over boosting As of this morning
Post by: yogibear on April 03, 2008, 09:19:31 PM
Went through all of the hoses tonite, took them all off the car and checked them. Low and behold one had a split in it.

Replaced and put it all bck to gether and its all boosting fine now.

1.3bar boost was good fun though.

Thanks all 4 your help solving.