Platypus

Thanks for those ideas. I just contacted Toyota again and the service manager said that they put a fuel pressure gauge in the fuel line. I left it there for two days. They started it after the first day and no coughing. The fuel pressure was still up within spec. The same the second day and no coughing. The TRD Aurion has no fuel return line. A week ago I used "LubeMobile" who did an on car clean of injectors and overhead gear and pistons. They use "Chem Tune" - it's about a 500ml can which is mixed with fuel to 50% then poured into a steel pressure vessel with a pressure gauge - the fuel line is disconnected and this pressure vessel supplies the fuel - they hang this from the bonnet clip, inject 30psi air and start the engine until it runs out. The chem tune injection line has a sintered metal end on the 2mm SS transfer line. This procedure is repeated with this capillary inserted under the throttle body boot so the fuel mix now injects - at 15psi this time- into the intake manifold via the supercharger. Revs are kept up at about 2000rpm during this part as the mixture is very rich. Of course the fuel pump power is disconnected - either pull the plug, under the cover plate under the back seat, or easier, pull the EFI2 15A fuse (blue one) - I checked the circuit schematic at Toyota for this. I have done a lot of homework on this problem and the injector guys all say that these injectors are a problem and can carbon up - the removal, spray pattern check to find the culprit then ultrasonic clean and Oring replacement is the only way to fix this for sure. I will need to find out if the supercharger needs to be removed - but it looks as if the fuel rail line can be loosened and the injector unclipped - the injectors need to go down straight as they have a long nozzle. The question right now is - do we need to remove the supercharger?

Toyota checked fuel pressure - reported it was fine. Plugs ok No diagnostics on the computer. Remember it only does this occasionally and only once at the first start of the day. There is only one thing left to do - remove and clean the injectors. The injector service tech looked up the injector for this car and said they do give trouble - well maybe some do! I recently used a mobile "chem-tune" but the next morning the car still coughed on start. Next is to use a mobile Injector cleaning tech( who doesn't remove the injectors - I will need to get that done) - remove the injectors, check spray pattern, ultrasonic clean and replace Oring seals. Has anyone done this - is it necessary to remove the supercharger? I have asked my local Toyota service manager - but he could not find any information on how to do this - so quite pointless asking Toyota to do the job.

Its been doing this on and off for a while - the first start, in the morning it will cough once or twice before it starts. Then it's fine all day for any number of starts. I have taken it in to Toyota twice to get diagnosed, but there are no codes, and they don't get the coughing issue even left for 2 days - and that's strange. I have asked Grand Motors at Southport but they had never heard of the issue happening. Has anyone had this issue?

I found that a broken plastic nipple for the Vacuum Switching valve (VSV) on the front of the air box caused coughing on cold start if the vehicle had been sitting a day or two. At times it would not start first time at all. It seems that some time ago, someone had inadvertantly broken the plastic nipple right on the air intake box - which can't be seen as the rubber hose covers the issue. In my case, a mechanic had superglued the rubber hose to the box body without repairing the nipple, which is really impossible to glue without sleeving it. Recently, enough was enough after taking it to my local dealer who couldn't replicate the problem, I had a shot at repairing it. Using a piece of a stainless steel 18 gauge hypodermic needle (which had the perfect internal diameter), i drilled out the broken plastic nipple and the part of the air box then superglued the assembly - it sealed perfectly. Some Inox on the rubber hose and the repair was done. What I can't find is a repair manual for the TRD - even Grand Motors tell me that TRD don't supply one - how do they do their repairs? I have attached a Camry Manual for the Intake control system - I coundn't find one for the TRD but the Camry is the same. If there is a repair manual out there please post Toyota Vacuum Switching Valve.pdf

I have owned a TRD SL3500 for 3 years(from new). We flew to Melbourne to pick it up and drive it back home( northern NSW). I hope no one out there has gone through this, but it certainly happened to me. The supercharger belt was noisy for the entire 1800Km trip home - as we left, the salesman said it would soon quiet down. When we arrived at Albury the front end started to get a little rumble. Grand Motors replaced the faulty supercharger belt - it was the wrong profile. The front suspension bearings were faulty and had to be replaced. After around a year, the lower steering assembly was replaced (loose). Most of the suspension bolts were also loose - I was there when the mechanic had to tighten them all. I have had three changes of hubcaps - Toyota should sell sets of four for a dollar as the lugs keep breaking as the caps are almost impossible to remove. I even greased the lugs, which improved the issue but then the cap moved a little and eventually a lug broke off. Two weeks ago I called in to the local dealer, who sent the four faulty hubcaps back to the regional manager. The mechanics also took photos of the wheel jack problem which was just noticed( the first flat tyre since I owned the car). The jack will crush the side skirt if used. I am still waiting to hear from Toyota who are extremely slack in responding. In the meantime I had to modify the jack using 30mm angle iron - now it clears the skirt and the car can be jacked up. This will do until Toyota respond. The side skirts are held under the body extending within 5mm of the jack point lip. If a jack with any more than a 5mm wide lip is used it will crush the skirt at the underbody. Toyota even got the tyre pressures wrong - I use 48psi front and 42psi rear. I started out using the recommended pressures but the tyres scrubbed out. How could TRD have made so many design errors with this car?