Friends, I have a problem in my car since last week, I recently order the middle part of exhaust system to replace the leaky part but during the dismantling process mechanic broke the rear part as well. Got the rear part but during fitting process fitter removed the rusted threaded bolt and amended by drilling bigger hole in the front part of exhaust and managed to joint with thinner bolt. When he started engine, noticed that exhaust was leaky from the joint so he putted a compound to repair the leak.

After the above change car was lack in power, check the relevant plastic pipes for any leak under the bonnet but all seems okay. I am not sure that what is the cause of the problem? There is no engine management light, I suspect if this problem is related with any sensor then I should get engine check warning light etc.

I can only suspect some thing related to exhaust system? Any one can point me in right direction or area with suggestions?

Plugs and distributor is less than 6 months old quite new, however I did not change plug leads since I bought this car, over 10 years.

Please help if you can thanks in advance.

Car details: Spacewagon, GLXi, 1994, 2.0 manual transmission

Were all the oxegen sensors reinstalled or replaced. Maybe the wires were damaged with all Knocking and drilling perhaps?

if too much sealing paste is used it can expand into the exhaust and cause a restriction always better if possible to use a gasket.
also a leaking exhaust will also provide more power as the gases have less distance and restrictions to travel past and allow the engine to breath better.

Hi members,
I checked the catalytic convertor blockage by removing manifold pipe to release the gases not through the exhaust and cat but the revs did not go up with application of gas. my mechanic suspected that might be TPS (Throttle Position Sensor). Anyone can relate my car problem with TPS? If this sensor fails do you get identical symptom or not? I need to buy a second hand Throttle Unit to check now. Anyone could suggest some thing different?

Regards

because the tps is only a potentiometer if it fails then it should trigger the warning system.
try using some strong fuel/cat cleaner in the system first as i also had to replace the middle boxes for the mot then found out that the cat had coked up causing it to loose power and be a right pain with the emissions test.
also if you decide to spray clean the throttle body be very careful of the bypass hole as the solvent can damage the air valve and causes the revs to run double idle

I replaced two parts throttle body nd ECU from identical car to role out TPS and ECU but problem stay with car. I am of the opinion that problem is with blockage in exhaust, especially in catalytic part or carbon deposition on the manifold part of the exhaust? I almost run out of ideas now any more suggestion. I think any other sensor if not work correctly then I should get engine check light but only blockage in exhaust will not generate message on the dash board.
Do you recommend replacing cats and cleaning of pipe link between manifold and catalytic convertor? Normally deposition of carbon could cause loss of power, what is your opinion?

Can any member specifically share experience with cats blockage symptom?

keeping the revs of the car at 2500 whilst parked up for ten to fifteen minutes will heat up the cat and help it to decoke also there are some cleaners that will do cats aswell as fuel system but not many as people tend to just replace the cat your local autospares should have some cleaner that will do the job.
for exhausts and some bits try http://www.onlineautomotive.co.uk/ as they were the cheepest when i had to replace part of my exhaust.

Hi Members,

Just need to update you that at last I found the problem with my space wagon. Distributor coil was arching and hence loosing current in the process and signal was not changing with gas. Ignition car parts repaired it and seem working correctly now. I would like to thanks members they reply and suggested actions to sort the problem. I think ECU takes a little while to learn and control car properly. I noticed after all above mentioned changes car is not settling revs at stationary position. Any logical reason for that?
:banana: