OK so finally got everything connected back up after taking the uim off, replaced all the hose\'s to the crv and my loss of boost is fixed, kinda. Now on WOT over 6000rpm i\'m getting hesitation, tried twice and it happened both times so i drove home like a granny just in case anything major was wrong. I got fully boost on the 1st turbo no probs btw.
I recently changed my plugs, 7\'s and 9\'s, fitted magnacor leads last year, fuel filter was changed about 4K ago (reason i mentioned these is i did a search and these seem to be a common fault). I seen that the wiring to the fuel pump if faulty can cause this but is there anything i may have knocked or loosened in the engine bay that would cause this problem?
Tomorrow i\'m planning on taking the leads off and checking them as some coolant was split on them when removing the uim but is there anything else to look out for?
what boost were ya hitting? could it be overboosting and fuel cut?
matt
My main theory would be an ignition problem. What boost are you running?
the cars been running 14psi since i got it, was seeing that maybe a little shy of the full 14.
The car rev\'s all the way the red line no probs without load, i dropped the clutch as soon as it hesitated and gave it a little to see what would happen. No probs there, it was an easy climb then a WOT attemp, all i got was the exhaust popping and flames as per usual.
I agree with nikp, I think the spark may be getting blown out or i\'m getting a missfire, but i could be wrong so if anyone can think of anything else...
Although, thinking about it, i did change the fuel level stop .... thingie a while back so i\'ll check the earth to the fuel pump tomorrow too.
The earths seem fine, not loose and are touching metal (is that right or should I check something else?)
After reading up on the american sites they mentioned heat may be a factor so tried a full runs when warmed up and when hot after sitting in traffic and no change. However the car does pull ok for the 1st run but any further runs cause the hesitation.
Tonight i noticed that the exhaust mades the same popping/crackling noise when it hesitates as it does when i hit redline so could it be fuel cut? And if so what would be the main causes?
I\'ve checked the boost sensor and it seems fine (ie it plugged in).
Also i was wondering about the 3 oneway check valves the connect to thr front of the uim, do these need to be connected to a specific nipple (there are 3 they connect to, running, 2 along the top and 1 under the right hand nipple) or can they just connect to any of the 3 nipples? Only mention these as they were the one thing that confused me when putting the uim back on (only the 4th time i\'ve done it in 3 1/2 yrs so i\'m not expert on this btw)
can anyone help please?
Turn the boost down to 10 psi and see if you still get hesitation first of all.
Next take out the plugs and inspect them post pics on here
check the Magnecor plug leads,they are notorious for not seating properly!
As Mark said plugs probably need changing too,put 9\'s all round.
Regards
Carl
Plugs were changed 3 weeks ago so i\'m doubting it\'s that but i\'ll drop them out just in case. Pics to follow
I\'ll doube check the magnacor keads, they can be buggers to fit correctly Carl.
I\'m not running a boost controller so have no way of turning down the boost.
Current set up is knightsport ecu, 14psi but i have a pressure regulator so most of the solenoids only see 10psi, de-cat, racingbeat exhaust (2 1/2 inch), xs power i/c. I\'ve been running this set up for over 2yrs and not had any major probs (apart from a knackered solenoid, hence the pressure regulator)
ok some pics of the plugs, first the trailing:
(http://i115.photobucket.com/albums/n289/Bobbit79/DSCI0082.jpg)
(http://i115.photobucket.com/albums/n289/Bobbit79/DSCI0083.jpg)
(http://i115.photobucket.com/albums/n289/Bobbit79/DSCI0084.jpg)
(http://i115.photobucket.com/albums/n289/Bobbit79/DSCI0086.jpg)
and the leading:
(http://i115.photobucket.com/albums/n289/Bobbit79/DSCI0088.jpg)
(http://i115.photobucket.com/albums/n289/Bobbit79/DSCI0087.jpg)
(http://i115.photobucket.com/albums/n289/Bobbit79/DSCI0089.jpg)
(http://i115.photobucket.com/albums/n289/Bobbit79/DSCI0090.jpg)
Gave them a good scrubbing with the wire brush and put them back in. One of the trailing leads seemed a little loose so made sure they are all tightly fitted.
Sounding odd, it\'s not the old alarm wiring issue is it?
Someone spliced a nice 30amp wire to an alarm in your 90 ignition wire??
Rumour has it that kicks in (if it does - some believe it is an issue, some don\'t) at around 5500rpm or just above...
dont think it is bud, the alarm has been fitted for 3yrs and never had any probs with it.
What are you looking for on the spark plugs Mark?
Also noticed on the way to work today that the boost seems a litle high, recently fitted a new boost guage but it seems quite slow to react to the actual boost so i\'m gonna put the old one back on and see what i\'m actually running. So it might be overboost which i think would be down to either a trapped pipe in the rats nest or a pipe has come off in the rats nest.
It makes sense, if i\'m right too much boost causes fuel cut doesn\'t it?
Quote from: Bobbit;609116Also i was wondering about the 3 oneway check valves the connect to the front of the uim, do these need to be connected to a specific nipple (there are 3 they connect to, running, 2 along the top and 1 under the right hand nipple) or can they just connect to any of the 3 nipples? Only mention these as they were the one thing that confused me when putting the uim back on (only the 4th time i\'ve done it in 3 1/2 yrs so i\'m not expert on this btw)
can anyone tell me the answer to this? Are the nipples just that, or do the correct pipes need to be connect to the correct nipple?
Thanks for the advice so far guys. :driving
anyone there?
Plugs look ok tbh, shame you cant lower the boost so you can see if there is an ignition problem or not, you may have to stick it on the dyno to diagnose
I concur about the plugs - they look fine.
Right so started taking the manifold off tonight, spotted a pipe that had popped off the very front single solenoid so that may have been the cause, planning on still taking the manifold off tomorrow to ensure everything is as it should be.
Sound\'s like a good time to get all your goodies bolted up and mapped matey, Enjoy it for the summer :-)
ok so over the bank holiday weekend I checked out the rats nest and all is connected, no splits or cracks, everything is connected to the right part AFAIK. I\'ve changed all the pipes to the crv so i know there are no splits there either. Could it be my boost sensor is faulty and that is causing my problems?
I can hear boost leaking from the crv between 3500-4500 rpm but then I can hear the boost leak stopping and starting about 4-5 times in very quick sucession, like a woosh, woosh, woosh, woosh, woosh. Lasts about 2-3 seconds but then I get about 7-9psi of boost. Then if i try again i get what seems to be fuel cut with the car hesitating and the exhaust popping etc.
My probs started with these leak but I thought it was a solenoids, after taking the UIM off and replacing it i now get the hesitation/fuel cut. So could the boost sensor be faulty or could it be something i\'ve not thought of?
Thanks
Have you tried doing the pin/led test to see if your ecu is complaining of any sensors out of range/shorted? I also seem to remember reading that one of those vac nipples at the read of the upper manifold vents to atmosphere. Never did check it though! (Saw it on Rx7club)
the what test?
Dont think any of the nipples should just vent as you\'ll just be loosing prreesue in the UIM, i was just wondering it the one way valves needed connecting to a specific nipple of if any would do.
Would a knackered fuse cause these probs?
Also as i\'ve got a new denso fuel pump from a supra will it be safe to drop that in or will that likely make things worse?
The l.e.d. test mate, it involves using a paperclip to short out two connection in your diagnostic port and then using an led to count the number of flashes which equates to an error code.
Ok, thanks Neil. I\'d have a look to see if I can find a how to.
If it is your map sensor that is at fault, i have my old one hanging around.
TBH bud i havent a clue what the fault is but if i can rule things out then it leaves me less to check. How much do you want for it?
did you ever sort this out? i have exactly the same issue! i just removed and replaced my uim im thinking i have some sort of boost leak will drive fine, idles a bit low and rough rev it and you can see black smoke (fuel) coming out the exhaust freely... drive it and you get to 5-6k and it seems to hesitate and hold back like i would expect a fuel cut, out of gear it will rev to redline easy....