Menu
Home
Post Something
Forums
Current Activity
New posts
Search forums
What's new
New posts
Latest activity
News & Features
The Marketplace
Cars for Sale
Engine and Performance
Chassis and Wheels
Exterior and Body
Interior and Cockpit
ICE - In Car Entertainment
Car Shops and Services
Toys and Wares
All Other Stuff
Jobs and Vacancies
Looking For
Members
Log in
Register
What's new
Search
Search
Search titles only
By:
Current Activity
New posts
Search forums
Menu
Log in
Register
Reply to thread
See what others are reading now! Try Forums >
Current Activity
Home
Forums
Main Forums
Car Talk
Forced Induction & Engine Management
CD5A 4G93T (WOT problem)
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Message
<blockquote data-quote="hamsap" data-source="post: 801830" data-attributes="member: 1832"><p>Hi guys,</p><p></p><p>Have gotten into some problems with the car jerking when WOT.</p><p></p><p>Engine - CD5A 4G93T</p><p>Stock form</p><p>ECU: 5663</p><p>Manual (if that helps..)</p><p></p><p>When WOT, I noticed that the boost comes in much earlier but the car is not pulling/ moving. We've gotten the spark plugs changed and gapped correctly (factory recommendation of 0.7mm - 0.8mm), gotten a wideband dynojet A/F meter strapped on and the A/F ratio seems fine (WOT reads around 11 - 12.5)</p><p></p><p>The next thing we did was rewire the fuel pump to get its electric supply directly, hence making it work more efficiently. Worked ok for a day, and the next day the same problem persist: Gradual acceleration on the accelerator= fine. WOT=bogs down the car, not accelerating as it used to be but I noticed boost comes in much earlier.</p><p></p><p>Ok, we have come to a few possibilities on why is this happening:</p><p></p><p><u><strong>1.)Fouled spark plugs</strong></u></p><p>Couldn't be cause the plugs are only 2 weeks old. Rating is 7, used 6 previously and it lasted me for only 2 weeks before it started misfiring </p><p></p><p>http://www.4gtuners.com/forums/style_emoticons/default/smile.gif</p><p></p><p>Properly[/URL] gapped at 0.8mm proportionately on all four plugs</p><p></p><p><u><strong>2.)Faulty internal wastegate/ boost actuator</strong></u></p><p>Boost reading stayed constant at 0.6 - 0.7 all the time. Now if it is jammed, then I would be reading a higher boost. If the wastegate actually opens up to earlier, wouldn't I see a lower boost reading or a boost reading something like 0.6 then 0.4 and then 0.6 again?</p><p></p><p>What I'm trying to say here is that if the actuator opens up the wastegate much earlier then it's suppose to be, I shouldn't be seeing a constant 0.6 bar of boost right?</p><p></p><p><u><strong>3.) Faulty fuel pump</strong></u></p><p>This might be the problem, I dunno. Just need to see if any one of you have faced such problems before. Now if it's a faulty fuel pump (or for that matter, injectors, FPR, fuel rail) which is not delivering enough fuel to the engine, I would be seeing a A/F ratio reading of 11 - 12.5 right?) Or is this because the ECU is somehow smart enough to detect there isn't enough supply of fuel and hence retard the timing?</p><p></p><p>My car is the second car that is facing such problems. Mech is still cracking up his head trying to figure out what's wrong, so hopefully there is someone who had faced such similar problems would be able to shed some light</p><p></p><p>P/S; Fuel filter has been changed last 3-4 weeks ago</p><p></p><p>Thanks!</p></blockquote><p></p>
[QUOTE="hamsap, post: 801830, member: 1832"] Hi guys, Have gotten into some problems with the car jerking when WOT. Engine - CD5A 4G93T Stock form ECU: 5663 Manual (if that helps..) When WOT, I noticed that the boost comes in much earlier but the car is not pulling/ moving. We've gotten the spark plugs changed and gapped correctly (factory recommendation of 0.7mm - 0.8mm), gotten a wideband dynojet A/F meter strapped on and the A/F ratio seems fine (WOT reads around 11 - 12.5) The next thing we did was rewire the fuel pump to get its electric supply directly, hence making it work more efficiently. Worked ok for a day, and the next day the same problem persist: Gradual acceleration on the accelerator= fine. WOT=bogs down the car, not accelerating as it used to be but I noticed boost comes in much earlier. Ok, we have come to a few possibilities on why is this happening: [U][B]1.)Fouled spark plugs[/B][/U] Couldn't be cause the plugs are only 2 weeks old. Rating is 7, used 6 previously and it lasted me for only 2 weeks before it started misfiring http://www.4gtuners.com/forums/style_emoticons/default/smile.gif Properly[/URL] gapped at 0.8mm proportionately on all four plugs [U][B]2.)Faulty internal wastegate/ boost actuator[/B][/U] Boost reading stayed constant at 0.6 - 0.7 all the time. Now if it is jammed, then I would be reading a higher boost. If the wastegate actually opens up to earlier, wouldn't I see a lower boost reading or a boost reading something like 0.6 then 0.4 and then 0.6 again? What I'm trying to say here is that if the actuator opens up the wastegate much earlier then it's suppose to be, I shouldn't be seeing a constant 0.6 bar of boost right? [U][B]3.) Faulty fuel pump[/B][/U] This might be the problem, I dunno. Just need to see if any one of you have faced such problems before. Now if it's a faulty fuel pump (or for that matter, injectors, FPR, fuel rail) which is not delivering enough fuel to the engine, I would be seeing a A/F ratio reading of 11 - 12.5 right?) Or is this because the ECU is somehow smart enough to detect there isn't enough supply of fuel and hence retard the timing? My car is the second car that is facing such problems. Mech is still cracking up his head trying to figure out what's wrong, so hopefully there is someone who had faced such similar problems would be able to shed some light P/S; Fuel filter has been changed last 3-4 weeks ago Thanks! [/QUOTE]
Insert quotes…
Verification
Post reply
The Marketplace Latest
original rare Rays Volk Racing TE37SL Black Edition...
Started by
david tao
Chassis and Wheels
Honda city JSracing gtwing spoiler
Started by
jeff6126
Exterior and Body
Honda civic fd ~car spray(Ferrari red)
Started by
jeff6126
Exterior and Body
Honda jazz fit gk flrs body kit
Started by
jeff6126
Exterior and Body
BMW F10 ~M5 front skirt lip with glossy black
Started by
jeff6126
Exterior and Body
Kia Forte gtwing spoiler
Started by
jeff6126
Exterior and Body
BMW F30 M3 front skirt lip
Started by
jeff6126
Exterior and Body
Proton Saga VVT Evo Front Bonnet Hood
Started by
jeff6126
Exterior and Body
Perodua bezza gear up body kit/spoiler
Started by
jeff6126
Exterior and Body
BMW F10 ~M5 front bumper set ~M5 kidney grille...
Started by
jeff6126
Exterior and Body
Posts refresh every 5 minutes
BMW's M Divison boss officially confirms M prepped 1-Series to be introduced soon
https://www.zerotohundred.com/wp-content/uploads/2010/06/bmw-1-series-tii.jpg
You have probably heard this story before about BMW working on a M-badged variant of the 1-Series. In fact it's been going on for years...
S15 Spec R 6speed tranny problem
anyone faced this problem b4?
don think my bro's 6speed gear box is right
n to tell the truth, the car is used for drift n track purpose
any solution for this if this 6 speed tranny is really weak?
such as go for...
How to remove PV6 front bumper?
Hi all, i'm planning on to retrofit my Perdana V6 headlamps but it seems that I need to remove my bumper to get the headlights out...anyone here familiar with removing a PV6 bumper? Thanks...:wavey:
Recent Posts
Darker Design : Mercedes-Benz Launches GLA Nightfall Edition in Malaysia
Started by
The_Mechanic
News and Features
Honda Malaysia Doubles Down on Hybrids: New CR-V Launches with Dual e:HEV...
Started by
The_Mechanic
News and Features
BateriHub Reaches 200-Store Milestone, Becomes Malaysia’s Largest...
Started by
The_Mechanic
News and Features
Been stalking for 3 years edy
Started by
dheepadarshan95
Introduction and Newbies
Recommendation: Turbocharger for 4B11 N.A engine
Started by
Mitevo7
Car Modification
Search
Online now
Enjoying Zerotohundred?
Log-in
for an ad-less experience
Home
Forums
Main Forums
Car Talk
Forced Induction & Engine Management
CD5A 4G93T (WOT problem)