SprintStar

Hello All,

I have a '86 RoW RHD 951.

About 2 years ago, I had this fuel cutting out problem but I never got around to solving it as Cylinder 1 liner developed a crack and I had to replace the block.

I took my time and finally I fired her up 2 weeks ago. She ran ok and the problem did not rear its ugly head so I assumed it was a bad connection at some connector end that got put right when I took out the old block and put in the replacement.

However, I did noticed that on occasion, the fuel would lean out but on giving more throttle, it went to the rich end again. I have a duty cycle monitor which also has a lean/rich LEDs. I know it's not accurate but I did put in a wide band and the results were similar.

Today, when going uphill and the engine died, my passengers joked about my clutch control and I laughed along but later on level ground, it started stumbling again and it's the same hell repeating!

I noticed the duty cycle will be more for the same throttle position and it would stumble and go lean. I changed out a DME relay with no effect.

Could it be a failing fuel pump? What other things could I check?

Thanks! And have a good weekend ahead!

Sprint.

SprintStar

Just to add, if I were to keep the revs up, it seems to clear the 'blockage' and be ok for a bit, then the problem comes back again. And if it were to die at the lights, waiting for a few minutes would then work again.

MAF?

Thanks.

Sprint.

xsboost90

are you running a stock air flow meter? ive seen them get "junk" in them and the door starts sticking. This will do exactly what you describe.

MM951

Clogged fuel filter? Only $17 and I changed mine and it solved a similar driveabilty problem I had

SprintStar

I'm using a Huntley Racing MAF which was already on the car when I got it.

I'll change out the fuel filter to eliminate things.

Plus I've also heard good things about the Vitesse MAF. I may get it, though I thought John was a bit curt in his email. I do understand he's a busy man though.

Sprint.

95ONE

Felt the same way. Nicer on the phone.

SprintStar

Do you have his number? I've looked on his website but none there. I did email him asking about injectors and I got a curt reply. I offered to call from Singapore but he mentioned something about spending too much time on the phone where he could do a lot more on email.

Anyway, I've been hearing good things about his MAF. I'm keep on it.

Sprint.

SprintStar

Just had the fuel filter changed out. 952 hasn't acted up yet in the last 4 hours. I'm keeping my fingers crossed.

Anyway, I have the Huntley Racing MAF and Split Second ARC2. I hear from some it's ancient stuff?

Isn't a MAF a MAF a MAF? I gotta convince myself to get a new one, so help me here!

Sprint.

lart951

Could be the DME it self, need to oppened and re solder some of the cracked connections due to heat and age.

Tom M'Guinn

Well, it could be lots of things of course (harness, dme, fpr, pump, etc.), but I will tell you I had what sounds like a similar problem when I used to run the HR MAF and ARC2. In my case, it could stumble maybe once a month or less, so was very difficult to track down. I never confirmed with 100% certainty, but did suspect it was the ARC2 had the electricial glitch -- bad solder joint, etc. I finally switched over to the Vitesse MAF/piggyback and have never had the problem again after several years! Even if that's not the issue, a modern digital MAF controller system is gives you so much more control than that ARC2 -- highly recommended.