DC_ Posted June 3, 2008 Share Posted June 3, 2008 Hello again all you knowledgable people, i have recently changed my exhaust as it was blowing like mad. Now has a rimmer brothers stainles steel system on it. Ok so, After putting it all together it has been blowing a bit at the manifold tubes, new bolts ordered and done them up and that seemed to EASE the blowing. After a drive or 2 i have now learned that it's blowing from the joins from the tubular manifold down to the Y peice. I did put assembly paste on when fitting but maybe not enough. So after this i have noticed that when i run on petrol it starts great, then settles down and cuts out, after restarting it idles JUST!! then runs very rough. When i drive on petrol it's defo losing power as you put the foot down, it goes, but then it's as if it struggles. I change over to gas and it runs ok. Have tried to change the filter on the petrol but with no joy as i couldn't get the nuts undone so will have a go at that again soon. Do you guys think it could be the fitting of the exhaust? Cheers Charlie Quote Link to comment Share on other sites More sharing options...
q-rover Posted June 3, 2008 Share Posted June 3, 2008 I take it the vehicle was running fine before the exhaust change? I would make sure it is fitted properly first, ie no leaks, before random guessing. Quote Link to comment Share on other sites More sharing options...
disco_al Posted June 3, 2008 Share Posted June 3, 2008 don't forget as well that a stainless performance type exhaust will extract the gasses faster than a standard system. what type of air filter is it? standard or K & N style? you may find that you will have to fit a cone type filter, or "performance" free flow filter to compensate for the exhaust. it would also pay to get the emmissions checked now that you have changed it. i may be completely wrong, but from my "normal" car tuning days, this is what i found after switching to a stainless system, because the engine breathed out better, it needed a higher air flow to comensate Quote Link to comment Share on other sites More sharing options...
DC_ Posted June 3, 2008 Author Share Posted June 3, 2008 Yeh it had a hole in the previous exhaust so wasn't the best but running no where near as bad as it is now. Cheers Quote Link to comment Share on other sites More sharing options...
DC_ Posted June 3, 2008 Author Share Posted June 3, 2008 Hi Al, i have the normal air filter fitted. I'll get the system fitted properly and see how that goes, then do filter and then see if the K&N makes a diff. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted June 3, 2008 Share Posted June 3, 2008 Just take your existing filter off to test, it's virtually the same as K&N then anyways! Oh... as you are on LPG, K&N filters are NOT recommended on a draw through system, they do not allow the engine to give enough suck at the mixer ring, therefore weakening the mixture substantially.... cue backfires! Try blocking off the exhaust pipe exit if you think that it is too free flowing for the engine, this should make it run better if that is the fault... TBH, I'd put money on a wire or two being knocked off during the exhaust installation, as it runs OK on gas, you can discount any of the ignition system, and I'd start by looking at things like your fuel pump feed wire, lambda probe (assuming you have one?) and also all of your LPG installation wiring, it MAY be that you have gas and petrol going into the cylinders at the same time, not good! Hope that helps! Quote Link to comment Share on other sites More sharing options...
DC_ Posted June 3, 2008 Author Share Posted June 3, 2008 Changed the fuel filter there and no difference so now i know that's not the problem and it could have been doing with it anyway. Really hard to describe..................starts ace!! then runs and coughs and plutters and cuts out on first idle, starts back up ace and coughs and plutters, if i keep tapping the accelerator it runs ok but you can hear the blowing and to be honest i think the manifolds are blowing too, Should i have put any kind of sealant on the gaskets when refitting the manifolds?? I'll double check for wires being pulled out etc but it was fairly easy and i only had to take off the airflow meter,few heat shields and that was about it, it doesn't have a lamba sensor on it either. I'll try blocking up the exhaust and also take the filter off completely to see if that improves things, at least that'll give me an idea of what the problem is. Cheers Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted June 3, 2008 Share Posted June 3, 2008 Hmm airflow meter plug can get crusty inside, and give the symptoms you describe, might be worth giving it a wiggle, and check that the single black wire from the airflow meter loom is connected securely to the coil -these have a habit of being left off, especially by me and should cut the engine if disconnected... a poor connection might give you the problems you are experiencing.... Also, vacuum leaks! easy to knock a pipe off, and while LPG might run 'OK' it is not as sensitive as Petrol, as it doesn't use the AFM. Check the hose between the AFM and the plenum for splits... Quote Link to comment Share on other sites More sharing options...
DC_ Posted June 4, 2008 Author Share Posted June 4, 2008 Will do, i was lying last night going through all the stuff i had to do in order to get the new manifold section in. When i was tightening up the bolts on the manifold i had to rest against the hose to the plenum chamber so i'll check incase i've peirced it and also all other hoses. Everytime i take the AFM plug off i clean it and spray with WD40 just to make sure it gets a good connection but i'll recheck everything. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted June 4, 2008 Share Posted June 4, 2008 Good luck, and take a big torch Quote Link to comment Share on other sites More sharing options...
DC_ Posted June 4, 2008 Author Share Posted June 4, 2008 Good luck, and take a big torch Right wee update................Dont know if this will be of any use but i was also thinking about when i done the fuel filter, i only started it up and it ran rough.Would i need to take it a wee run or should it have made a difference straight away?? So tonight i went out and checked all wires pipes etc...........noticed one on the coil wasn't sitting secure although it was on, cleaned up the connections on the AFM and took out the air filter, started it up and it was still rough, went round the back and plugged up the exhaust and it still ran rough. So............i then took off the connection to the AFM whilst it was JUST ticking over, It nearly died but then burst into life, Settled down after running high for a few seconds and it ran much better, i put the AFM connection back on and it made no difference, ran ok. Still blowing mind......................So decided to take it a run round the block, man does it fly now on petrol No coughing or spluttering, good acceleration...............Stopped and put the filter back on, another test run................fine, same as without. Let it idle for a few mins and it seems to idle fine. Decided to switch over to LPG and it ran ok too, but when i changed back over to petrol it ran a little off again almost cutting out, Took off the AFM connection again and same thing happened, burst into life and ran better after reconnecting it............................Sorry to go on but i thought a good description of what exactly happened might make the solution easier if there is one. If it wasn't still blowing i would be in heaven with the way it ran tonight. What's the thoughts then?? Quote Link to comment Share on other sites More sharing options...
SteveRK Posted June 4, 2008 Share Posted June 4, 2008 Hi Bowie what's this Black wire from the air flow meter loom? Do you mean its connected to the MAF and coil or just in the loom that goes from the coil to the ECU via the MAF to provide the firing pulses and has the 6.8KOhm resistor in series? I dont have a black wire connected to my MAF and the manual doesnt show one either. Quote Link to comment Share on other sites More sharing options...
DC_ Posted June 5, 2008 Author Share Posted June 5, 2008 ?? Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted June 5, 2008 Share Posted June 5, 2008 Hi Bowiewhat's this Black wire from the air flow meter loom? Do you mean its connected to the MAF and coil or just in the loom that goes from the coil to the ECU via the MAF to provide the firing pulses and has the 6.8KOhm resistor in series? I dont have a black wire connected to my MAF and the manual doesnt show one either. Sorry, should have been more clear, the wire enters the same part of the loom that the AFM plug uses, you can see it in this pic here: I think technically it is a black with white, but as you can see it has a sleeve around it's whole length... Sounds like you AFM might have gone south DC_, When you disconnect it, the ECU goes into limp home mode, and won't reset until you stop the engine and restart it, or in your case, change to LPG and back to petrol (I suspect your LPG system is turning the ECU off somehow rather than switching the injectors -very common). In this state it will run, but very rich, and on tight corners in carparks for example it may well try to stall or hunt ... so not ideal, even though they do run OK on the road. If you have one I'd try swapping out for another and see if that helps... Good luck... Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted June 5, 2008 Share Posted June 5, 2008 It definitely doesn't have lambda sensors? The hotwire system self tunes for a while when it's first run after the battery has been disconnected - it course tunes for a few miles then stores settings and goes into standard fine tune mode. If you kick it over to LPG too soon it gets confused and stores a really bad course tune map which it then can't adjust enough when in fine tune mode. A blowing manifold would also affect the mixture it sees and confuse it (all the time, not just when tuning. The difference in running between hot and cold could be due to either cold start enrichment of the fuel mixture ending or heat expansion opening up the gaps in the manifold joints. Or could be a shot/disconnected coolant temperature sensor. If poking around semi-randomly hasn't found anything conclusive, it's time to go and find the hotwire diagnostics manual in the tech archive and work through it. It'll take you a while (lots of things to check), but it almost certainly will pin down the cause. Personally I'd start by fixing the known issue of the blowing manifold(s) before going looking for anything else. Quote Link to comment Share on other sites More sharing options...
DC_ Posted June 5, 2008 Author Share Posted June 5, 2008 Thanks guys, From what you say then i think th AFM may be to blame although i'll get the blowing sorted soon when i have time. I know of 3 RRC's that are being broken down so i will see if the AFM is up for grabs. Bowie, the pic is spot on exactly like mine, I still reckon it's got somit to do with the manifold etc........... so that's my first priority as it was running great before the exhaust change over. I can see if i can get the AFM from the other RRC's as it'll always come in handy no doubt. Cheers, no doubt i'llbe back to bug you's again Charlie Quote Link to comment Share on other sites More sharing options...
steve_d Posted June 5, 2008 Share Posted June 5, 2008 Did you put the exhaust manifold gaskets on the right way round? You can put them upside down or back to front. Net result is that they can both restrict the gas flow and fail to seal properly. Ask me how I know. Steve Quote Link to comment Share on other sites More sharing options...
V8david Posted June 6, 2008 Share Posted June 6, 2008 Did you put the exhaust manifold gaskets on the right way round?You can put them upside down or back to front. Net result is that they can both restrict the gas flow and fail to seal properly. Ask me how I know. Steve When I got mine it turned out one of the chimps on the assembly line had actually welded a bracket on upside down! No chance of ever getting a seal. I took it off and put in back on about 5 times before I realised. Problem was they are such a pain in the arse to get in and out it took me a year to finally REALLY loose my rag and yank the manifold out to discover the problem! Fair play to MM4X4 they sent another one but it didn't make up for all the blood, sweat and blue air! So like Steve said check your gaskets are the right way round and also check all the brackets are the right way round. I also highly recommend investing in a manifold fitting kit from Rimmers. Makes the job SO much easier, saves repeatedly screwing in and out of the cylinder heads to. Good luck mate. Quote Link to comment Share on other sites More sharing options...
DC_ Posted June 9, 2008 Author Share Posted June 9, 2008 Cheers guys, Hmmm i am a bit stumped at the gasket senario, as when it was off, we ried to see how they would go on, but...............there seems to be a flat side and a rounded side, I tried to get the flat side sitting on the engine but could only manage 2 of them on each side due to the bolt holes would not line up other wise??? Quote Link to comment Share on other sites More sharing options...
V8david Posted June 9, 2008 Share Posted June 9, 2008 Cheers guys, Hmmm i am a bit stumped at the gasket senario, as when it was off, we ried to see how they would go on, but...............there seems to be a flat side and a rounded side, I tried to get the flat side sitting on the engine but could only manage 2 of them on each side due to the bolt holes would not line up other wise??? Yeah that's right. As long as the bolt holes line up, and the port holes, they're ok. Quote Link to comment Share on other sites More sharing options...
DC_ Posted June 10, 2008 Author Share Posted June 10, 2008 Ahhh i see, so there will be 2 gaskets on each side that the rounded side is sitting on the exhaust and 2 sitting on the engine.? Quote Link to comment Share on other sites More sharing options...
V8david Posted June 10, 2008 Share Posted June 10, 2008 Ahhh i see, so there will be 2 gaskets on each side that the rounded side is sitting on the exhaust and 2 sitting on the engine.? Spot on mate. Check the joints where the manifolds go into the Y pipe underneath as well, make sure they're right in. Quote Link to comment Share on other sites More sharing options...
DC_ Posted June 10, 2008 Author Share Posted June 10, 2008 Good man, i think the only trouble i can remember having,was getting the Y joints to go together, so if i need to bend the bracket a bit so they can sit more true i'll do that. As far as i know now, the manifolds should be on right but i'm sure they are still blowing, so i'll need to double check all is ok, blooming pain on the rectorium Quote Link to comment Share on other sites More sharing options...
V8david Posted June 10, 2008 Share Posted June 10, 2008 Good man, i think the only trouble i can remember having,was getting the Y joints to go together, so if i need to bend the bracket a bit so they can sit more true i'll do that. As far as i know now, the manifolds should be on right but i'm sure they are still blowing, so i'll need to double check all is ok, blooming pain on the rectorium Yeah, best to have a double check of everything! I know what you're going through and it drove me insane for AGES! I swear that even when it is right you can still hear blowing noises in your head! Good luck with it because when it is right it sounds awesome and is well worth the mental torture! Quote Link to comment Share on other sites More sharing options...
DC_ Posted June 10, 2008 Author Share Posted June 10, 2008 As homer would say.............help me jebus!!! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.